tr_backend.cpp

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
Copyright (C) 2006-2011 Robert Beckebans <trebor_7@users.sourceforge.net>

This file is part of Daemon source code.

Daemon source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Daemon source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Daemon source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// tr_backend.c

#include "framework/OmpSystem.h"
#include "tr_local.h"
#include "gl_shader.h"
#include "Material.h"
#if defined( REFBONE_NAMES )
	#include <client/client.h>
#endif

backEndData_t  *backEndData[ SMP_FRAMES ];
backEndState_t backEnd;

static Cvar::Cvar<bool> r_clear( "r_clear", "Clear screen before painting over it on every frame", Cvar::NONE, false );
Cvar::Cvar<bool> r_drawSky( "r_drawSky", "Draw the sky (clear the sky if disabled)", Cvar::NONE, true );
static Cvar::Cvar<int> r_showEntityBounds(
	"r_showEntityBounds", "show bboxes used for culling (1: wireframe; 2: translucent solid)", Cvar::CHEAT, 0);

void GL_Bind( image_t *image )
{
	int texnum;

	if ( !image )
	{
		Log::Warn("GL_Bind: NULL image" );
		image = tr.defaultImage;
	}
	else
	{
		GLIMP_LOGCOMMENT( "--- GL_Bind( %s ) ---", image->name );
	}

	texnum = image->texnum;

	if ( r_nobind->integer && tr.blackImage )
	{
		// performance evaluation option
		texnum = tr.blackImage->texnum;
	}

	if ( glConfig.usingBindlessTextures ) {
		tr.textureManager.BindReservedTexture( image->type, texnum );
		return;
	}

	if ( tr.currenttextures[ glState.currenttmu ] != texnum )
	{
		image->frameUsed = tr.frameCount;
		tr.currenttextures[ glState.currenttmu ] = texnum;
		glBindTexture( image->type, texnum );
	}
}

void GL_Unbind( image_t *image )
{
	GLIMP_LOGCOMMENT( "--- GL_Unbind() ---" );

	tr.currenttextures[ glState.currenttmu ] = 0;
	glBindTexture( image->type, 0 );
}

GLuint64 BindAnimatedImage( int unit, const textureBundle_t *bundle )
{
	int index;

	if ( bundle->isVideoMap )
	{
		if ( bundle->videoMapHandle >= 0 && CIN_RunCinematic( bundle->videoMapHandle ) )
		{
			GL_SelectTexture( unit );
			CIN_UploadCinematic( bundle->videoMapHandle );
			return tr.cinematicImage[ bundle->videoMapHandle ]->texture->bindlessTextureHandle;
		}
		else
		{
			return GL_BindToTMU( unit, tr.defaultImage );
		}
	}

	if ( bundle->numImages <= 1 )
	{
		return GL_BindToTMU( unit, bundle->image[ 0 ] );
	}

	// it is necessary to do this messy calc to make sure animations line up
	// exactly with waveforms of the same frequency
	index = Q_ftol( backEnd.refdef.floatTime * bundle->imageAnimationSpeed * FUNCTABLE_SIZE );
	index >>= FUNCTABLE_SIZE2;

	if ( index < 0 )
	{
		index = 0; // may happen with shader time offsets
	}

	index %= bundle->numImages;

	return GL_BindToTMU( unit, bundle->image[ index ] );
}

void GL_BindProgram( ShaderProgramDescriptor* program )
{
	if ( !program )
	{
		GL_BindNullProgram();
		return;
	}

	if ( glState.currentProgram != program )
	{
		glUseProgram( program->id );
		glState.currentProgram = program;
	}
}

void GL_BindNullProgram()
{
	GLIMP_LOGCOMMENT( "--- GL_BindNullProgram ---" );

	if ( glState.currentProgram )
	{
		glUseProgram( 0 );
		glState.currentProgram = nullptr;
	}
}

void GL_BindVAO( const GLuint id ) {
	if ( backEnd.currentVAO != id ) {
		glBindVertexArray( id );
		backEnd.currentVAO = id;
	}
}

void GL_SelectTexture( int unit )
{
	if ( glState.currenttmu == unit )
	{
		return;
	}

	if ( unit >= 0 && unit < glConfig.maxTextureUnits )
	{
		glActiveTexture( GL_TEXTURE0 + unit );
	}
	else
	{
		Sys::Drop( "GL_SelectTexture: unit = %i", unit );
	}

	glState.currenttmu = unit;
}

GLuint64 GL_BindToTMU( int unit, image_t *image )
{
	if ( !image )
	{
		Log::Warn("GL_BindToTMU: NULL image" );
		image = tr.defaultImage;
	}

	if ( glConfig.usingBindlessTextures ) {
		return tr.textureManager.BindTexture( 0, image->texture );
	}

	int texnum = image->texnum;

	if ( unit < 0 || unit >= glConfig.maxTextureUnits )
	{
		Sys::Drop( "GL_BindToTMU: unit %i is out of range", unit );
	}

	if ( tr.currenttextures[ unit ] == texnum )
	{
		return 0;
	}

	GL_SelectTexture( unit );
	GL_Bind( image );
	return 0;
}

static void BlitFBOToMSAA( FBO_t* fbo, const GLbitfield mask ) {
	R_BindFBO( GL_READ_FRAMEBUFFER, fbo );
	R_BindFBO( GL_DRAW_FRAMEBUFFER, tr.msaaFBO );

	glBlitFramebuffer( 0, 0, fbo->width, fbo->height, 0, 0, tr.msaaFBO->width, tr.msaaFBO->height,
		mask, GL_NEAREST );

	R_BindFBO( GL_READ_FRAMEBUFFER, tr.msaaFBO );
}

static void BlitMSAAToFBO( FBO_t* fbo, const GLbitfield mask ) {
	R_BindFBO( GL_READ_FRAMEBUFFER, tr.msaaFBO );
	R_BindFBO( GL_DRAW_FRAMEBUFFER, fbo );

	glBlitFramebuffer( 0, 0, tr.msaaFBO->width, tr.msaaFBO->height, 0, 0, fbo->width, fbo->height,
		mask, GL_NEAREST );

	R_BindFBO( GL_READ_FRAMEBUFFER, fbo );
}

void TransitionMainToMSAA( const GLbitfield mask ) {
	if ( glConfig.MSAA ) {
		BlitFBOToMSAA( tr.mainFBO[backEnd.currentMainFBO], mask );
	}
}

void TransitionMSAAToMain( const GLbitfield mask ) {
	if ( glConfig.MSAA ) {
		BlitMSAAToFBO( tr.mainFBO[backEnd.currentMainFBO], mask );
	}
}

void BindMSAAOrMainFBO() {
	if ( glConfig.MSAA ) {
		R_BindFBO( tr.msaaFBO );
	} else {
		R_BindFBO( tr.mainFBO[backEnd.currentMainFBO] );
	}
}

void GL_BlendFunc( GLenum sfactor, GLenum dfactor )
{
	if ( glState.blendSrc != ( signed ) sfactor || glState.blendDst != ( signed ) dfactor )
	{
		glState.blendSrc = sfactor;
		glState.blendDst = dfactor;

		glBlendFunc( sfactor, dfactor );
	}
}

void GL_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
{
	if ( glState.clearColorRed != red || glState.clearColorGreen != green || glState.clearColorBlue != blue || glState.clearColorAlpha != alpha )
	{
		glState.clearColorRed = red;
		glState.clearColorGreen = green;
		glState.clearColorBlue = blue;
		glState.clearColorAlpha = alpha;

		glClearColor( red, green, blue, alpha );
	}
}

void GL_ClearDepth( GLclampd depth )
{
	if ( glState.clearDepth != depth )
	{
		glState.clearDepth = depth;

		glClearDepth( depth );
	}
}

void GL_ClearStencil( GLint s )
{
	if ( glState.clearStencil != s )
	{
		glState.clearStencil = s;

		glClearStencil( s );
	}
}

void GL_ColorMask( GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha )
{
	if ( glState.colorMaskRed != red || glState.colorMaskGreen != green || glState.colorMaskBlue != blue || glState.colorMaskAlpha != alpha )
	{
		glState.colorMaskRed = red;
		glState.colorMaskGreen = green;
		glState.colorMaskBlue = blue;
		glState.colorMaskAlpha = alpha;

		glColorMask( red, green, blue, alpha );
	}
}

void GL_DepthFunc( GLenum func )
{
	if ( glState.depthFunc != ( signed ) func )
	{
		glState.depthFunc = func;

		glDepthFunc( func );
	}
}

void GL_DepthMask( GLboolean flag )
{
	if ( glState.depthMask != flag )
	{
		glState.depthMask = flag;

		glDepthMask( flag );
	}
}

void GL_DrawBuffer( GLenum mode )
{
	if ( glState.drawBuffer != ( signed ) mode )
	{
		glState.drawBuffer = mode;

		glDrawBuffer( mode );
	}
}

void GL_FrontFace( GLenum mode )
{
	if ( glState.frontFace != ( signed ) mode )
	{
		glState.frontFace = mode;

		glFrontFace( mode );
	}
}

void GL_LoadModelViewMatrix( const matrix_t m )
{
	if ( MatrixCompare( glState.modelViewMatrix[ glState.stackIndex ], m ) )
	{
		return;
	}

	MatrixCopy( m, glState.modelViewMatrix[ glState.stackIndex ] );
	MatrixMultiply( glState.projectionMatrix[ glState.stackIndex ], glState.modelViewMatrix[ glState.stackIndex ],
	                glState.modelViewProjectionMatrix[ glState.stackIndex ] );
}

void GL_LoadProjectionMatrix( const matrix_t m )
{
	if ( MatrixCompare( glState.projectionMatrix[ glState.stackIndex ], m ) )
	{
		return;
	}

	MatrixCopy( m, glState.projectionMatrix[ glState.stackIndex ] );
	MatrixMultiply( glState.projectionMatrix[ glState.stackIndex ], glState.modelViewMatrix[ glState.stackIndex ],
	                glState.modelViewProjectionMatrix[ glState.stackIndex ] );
}

void GL_PushMatrix()
{
	glState.stackIndex++;

	if ( glState.stackIndex >= MAX_GLSTACK )
	{
		glState.stackIndex = MAX_GLSTACK - 1;
		Sys::Drop( "GL_PushMatrix: stack overflow = %i", glState.stackIndex );
	}
}

void GL_PopMatrix()
{
	glState.stackIndex--;

	if ( glState.stackIndex < 0 )
	{
		glState.stackIndex = 0;
		Sys::Drop( "GL_PushMatrix: stack underflow" );
	}
}

void GL_PolygonMode( GLenum face, GLenum mode )
{
	if ( glState.polygonFace != ( signed ) face || glState.polygonMode != ( signed ) mode )
	{
		glState.polygonFace = face;
		glState.polygonMode = mode;

		glPolygonMode( face, mode );
	}
}

void GL_Scissor( GLint x, GLint y, GLsizei width, GLsizei height )
{
	if ( glState.scissorX != x || glState.scissorY != y || glState.scissorWidth != width || glState.scissorHeight != height )
	{
		glState.scissorX = x;
		glState.scissorY = y;
		glState.scissorWidth = width;
		glState.scissorHeight = height;

		glScissor( x, y, width, height );
	}
}

void GL_Viewport( GLint x, GLint y, GLsizei width, GLsizei height )
{
	if ( glState.viewportX != x || glState.viewportY != y || glState.viewportWidth != width || glState.viewportHeight != height )
	{
		glState.viewportX = x;
		glState.viewportY = y;
		glState.viewportWidth = width;
		glState.viewportHeight = height;

		glViewport( x, y, width, height );
	}
}

void GL_PolygonOffset( float factor, float units )
{
	if ( glState.polygonOffsetFactor != factor || glState.polygonOffsetUnits != units )
	{
		glState.polygonOffsetFactor = factor;
		glState.polygonOffsetUnits = units;

		glPolygonOffset( factor, units );
	}
}

void GL_Cull( cullType_t cullType )
{
	if ( backEnd.viewParms.mirrorLevel % 2 == 1 )
	{
		GL_FrontFace( GL_CW );
	}
	else
	{
		GL_FrontFace( GL_CCW );
	}

	if ( glState.faceCulling == cullType )
	{
		return;
	}

	if ( cullType == cullType_t::CT_TWO_SIDED )
	{
		glDisable( GL_CULL_FACE );
	}
	else
	{
		if( glState.faceCulling == cullType_t::CT_TWO_SIDED )
			glEnable( GL_CULL_FACE );

		if ( cullType == cullType_t::CT_BACK_SIDED )
		{
			glCullFace( GL_BACK );
		}
		else
		{
			glCullFace( GL_FRONT );
		}
	}
	glState.faceCulling = cullType;
}

/*
GL_State

This routine is responsible for setting the most commonly changed state
in Q3.
*/
void GL_State( uint32_t stateBits )
{
	uint32_t diff = stateBits ^ glState.glStateBits;
	diff &= ~glState.glStateBitsMask;

	if ( !diff )
	{
		return;
	}

	// check depthFunc bits
	if ( diff & GLS_DEPTHFUNC_BITS )
	{
		switch ( stateBits & GLS_DEPTHFUNC_BITS )
		{
			default:
				GL_DepthFunc( GL_LEQUAL );
				break;

			case GLS_DEPTHFUNC_ALWAYS:
				GL_DepthFunc( GL_ALWAYS );
				break;

			case GLS_DEPTHFUNC_LESS:
				GL_DepthFunc( GL_LESS );
				break;

			case GLS_DEPTHFUNC_EQUAL:
				GL_DepthFunc( GL_EQUAL );
				break;
		}
	}

	// check blend bits
	if ( diff & ( GLS_SRCBLEND_BITS | GLS_DSTBLEND_BITS ) )
	{
		GLenum srcFactor, dstFactor;

		if ( stateBits & ( GLS_SRCBLEND_BITS | GLS_DSTBLEND_BITS ) )
		{
			switch ( stateBits & GLS_SRCBLEND_BITS )
			{
				case GLS_SRCBLEND_ZERO:
					srcFactor = GL_ZERO;
					break;

				case GLS_SRCBLEND_ONE:
					srcFactor = GL_ONE;
					break;

				case GLS_SRCBLEND_DST_COLOR:
					srcFactor = GL_DST_COLOR;
					break;

				case GLS_SRCBLEND_ONE_MINUS_DST_COLOR:
					srcFactor = GL_ONE_MINUS_DST_COLOR;
					break;

				case GLS_SRCBLEND_SRC_ALPHA:
					srcFactor = GL_SRC_ALPHA;
					break;

				case GLS_SRCBLEND_ONE_MINUS_SRC_ALPHA:
					srcFactor = GL_ONE_MINUS_SRC_ALPHA;
					break;

				case GLS_SRCBLEND_DST_ALPHA:
					srcFactor = GL_DST_ALPHA;
					break;

				case GLS_SRCBLEND_ONE_MINUS_DST_ALPHA:
					srcFactor = GL_ONE_MINUS_DST_ALPHA;
					break;

				case GLS_SRCBLEND_ALPHA_SATURATE:
					srcFactor = GL_SRC_ALPHA_SATURATE;
					break;

				default:
					srcFactor = GL_ONE; // to get warning to shut up
					Sys::Drop( "GL_State: invalid src blend state bits" );
			}

			switch ( stateBits & GLS_DSTBLEND_BITS )
			{
				case GLS_DSTBLEND_ZERO:
					dstFactor = GL_ZERO;
					break;

				case GLS_DSTBLEND_ONE:
					dstFactor = GL_ONE;
					break;

				case GLS_DSTBLEND_SRC_COLOR:
					dstFactor = GL_SRC_COLOR;
					break;

				case GLS_DSTBLEND_ONE_MINUS_SRC_COLOR:
					dstFactor = GL_ONE_MINUS_SRC_COLOR;
					break;

				case GLS_DSTBLEND_SRC_ALPHA:
					dstFactor = GL_SRC_ALPHA;
					break;

				case GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA:
					dstFactor = GL_ONE_MINUS_SRC_ALPHA;
					break;

				case GLS_DSTBLEND_DST_ALPHA:
					dstFactor = GL_DST_ALPHA;
					break;

				case GLS_DSTBLEND_ONE_MINUS_DST_ALPHA:
					dstFactor = GL_ONE_MINUS_DST_ALPHA;
					break;

				default:
					dstFactor = GL_ONE; // to get warning to shut up
					Sys::Drop( "GL_State: invalid dst blend state bits" );
			}

			glEnable( GL_BLEND );
			GL_BlendFunc( srcFactor, dstFactor );
		}
		else
		{
			glDisable( GL_BLEND );
		}
	}

	// check colormask
	if ( diff & GLS_COLORMASK_BITS )
	{
		GL_ColorMask( ( stateBits & GLS_REDMASK_FALSE ) ? GL_FALSE : GL_TRUE,
			      ( stateBits & GLS_GREENMASK_FALSE ) ? GL_FALSE : GL_TRUE,
			      ( stateBits & GLS_BLUEMASK_FALSE ) ? GL_FALSE : GL_TRUE,
			      ( stateBits & GLS_ALPHAMASK_FALSE ) ? GL_FALSE : GL_TRUE );
	}

	// check depthmask
	if ( diff & GLS_DEPTHMASK_TRUE )
	{
		if ( stateBits & GLS_DEPTHMASK_TRUE )
		{
			GL_DepthMask( GL_TRUE );
		}
		else
		{
			GL_DepthMask( GL_FALSE );
		}
	}

	// fill/line mode
	if ( diff & GLS_POLYMODE_LINE )
	{
		if ( stateBits & GLS_POLYMODE_LINE )
		{
			GL_PolygonMode( GL_FRONT_AND_BACK, GL_LINE );
		}
		else
		{
			GL_PolygonMode( GL_FRONT_AND_BACK, GL_FILL );
		}
	}

	// depthtest
	if ( diff & GLS_DEPTHTEST_DISABLE )
	{
		if ( stateBits & GLS_DEPTHTEST_DISABLE )
		{
			glDisable( GL_DEPTH_TEST );
		}
		else
		{
			glEnable( GL_DEPTH_TEST );
		}
	}

	glState.glStateBits ^= diff;
}

static void GL_VertexAttribPointers( uint32_t attribBits, const bool settingUpVAO ) {
	uint32_t i;

	if ( !glState.currentVBO )
	{
		Sys::Error( "GL_VertexAttribPointers: no VBO bound" );
	}

	GLIMP_LOGCOMMENT( "--- GL_VertexAttribPointers( %s ) ---", glState.currentVBO->name );

	if ( glConfig.vboVertexSkinningAvailable && tess.vboVertexSkinning )
	{
		attribBits |= ATTR_BONE_FACTORS;
	}

	for ( i = 0; i < ATTR_INDEX_MAX; i++ )
	{
		uint32_t bit = BIT( i );
		uint32_t frame = 0;
		uintptr_t base = 0;

		if( glState.currentVBO == tess.vbo ) {
			base = tess.vertexBase * sizeof( shaderVertex_t );
		}

		if ( ( attribBits & bit ) != 0 &&
		     ( !( glState.vertexAttribPointersSet & bit ) ||
		       tess.vboVertexAnimation ||
		       glState.currentVBO == tess.vbo || settingUpVAO || glState.currentVBO->dynamicVAO ) )
		{
			const vboAttributeLayout_t *layout = &glState.currentVBO->attribs[ i ];

			GLIMP_LOGCOMMENT( "glVertexAttribPointer( %s )", attributeNames[ i ] );

			if ( ( ATTR_INTERP_BITS & bit ) && glState.vertexAttribsInterpolation > 0 )
			{
				frame = glState.vertexAttribsNewFrame;
			}
			else
			{
				frame = glState.vertexAttribsOldFrame;
			}

			if ( !( glState.currentVBO->attribBits & bit ) )
			{
				Log::Warn( "GL_VertexAttribPointers: %s does not have %s",
				           glState.currentVBO->name, attributeNames[ i ] );
			}

			glVertexAttribPointer( i, layout->numComponents, layout->componentType, layout->normalize, layout->stride, BUFFER_OFFSET( layout->ofs + ( frame * layout->frameOffset + base ) ) );
			glState.vertexAttribPointersSet |= bit;
		}
	}
}

void GL_VertexAttribsState( uint32_t stateBits, const bool settingUpVAO )
{
	uint32_t diff;
	uint32_t i;

	if ( !settingUpVAO && glState.currentVBO && !glState.currentVBO->dynamicVAO ) {
		glState.currentVBO->VAO.Bind();
		return;
	}

	if ( glConfig.vboVertexSkinningAvailable && tess.vboVertexSkinning )
	{
		stateBits |= ATTR_BONE_FACTORS;
	}

	GL_VertexAttribPointers( stateBits, settingUpVAO );

	if ( !settingUpVAO && backEnd.currentVAO != backEnd.defaultVAO ) {
		return;
	}

	diff = stateBits;

	if ( backEnd.currentVAO == backEnd.defaultVAO ) {
		diff ^= glState.vertexAttribsState;
	}

	if ( !diff )
	{
		return;
	}

	for ( i = 0; i < ATTR_INDEX_MAX; i++ )
	{
		uint32_t bit = BIT( i );

		if ( ( diff & bit ) )
		{
			if ( ( stateBits & bit ) )
			{
				GLIMP_LOGCOMMENT( "glEnableVertexAttribArray( %s )", attributeNames[ i ] );

				glEnableVertexAttribArray( i );
			}
			else
			{
				GLIMP_LOGCOMMENT( "glDisableVertexAttribArray( %s )", attributeNames[ i ] );

				glDisableVertexAttribArray( i );
			}
		}
	}

	if ( backEnd.currentVAO == backEnd.defaultVAO ) {
		glState.vertexAttribsState = stateBits;
	}
}

static GLint GL_ToSRGB( GLint internalFormat, bool isSRGB )
{
	if ( !isSRGB )
	{
		return internalFormat;
	}

	auto convert = []( GLint format )
	{
		switch ( format )
		{
#if 0 // Not used in the code base.
			/* EXT_texture_sRGB_R8 extension.
			See: https://github.com/KhronosGroup/OpenGL-Registry/blob/main/extensions/EXT/EXT_texture_sRGB_R8.txt */
			case GL_RED:
				return GL_SR8_EXT;
#endif
			case GL_RGB:
				return GL_SRGB;
			case GL_RGBA:
				return GL_SRGB_ALPHA;
			case GL_RGB8:
				return GL_SRGB8;
			case GL_RGBA8:
				return GL_SRGB8_ALPHA8;
#if 0 // Internal formats, should not be used directly.
			case GL_COMPRESSED_RGB:
			 	return GL_COMPRESSED_SRGB;
			case GL_COMPRESSED_RGBA:
				return GL_COMPRESSED_SRGB_ALPHA;
#endif
			case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
				return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT;
			case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
				return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
			case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
				return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
			case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
				return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
#if 0 // Not used in the codebase,
			/* Core 4.2, ARB_texture_compression_bptc extension.
			See: https://github.com/KhronosGroup/OpenGL-Registry/blob/main/extensions/ARB/ARB_texture_compression_bptc.txt */
			case GL_COMPRESSED_RGBA_BPTC_UNORM:
				return GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM;
#endif
			default:
				return format;
		}
	};

	GLint finalFormat = convert( internalFormat );

	if ( finalFormat == internalFormat )
	{
		Log::Warn( "Missing sRGB conversion for GL format: %0#x", internalFormat );
	}
	else
	{
		Log::Debug( "Using sRGB GL format: %0#x", finalFormat );
	}

	return finalFormat;
}

void GL_TexImage2D( GLenum target, GLint level, GLint internalFormat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const void *data, bool isSRGB )
{
	GLint finalFormat = GL_ToSRGB( internalFormat, isSRGB );

	glTexImage2D( target, level, finalFormat, width, height, border, format, type, data );
}

void GL_TexImage2DMultisample( GLenum target, GLsizei samples, GLint internalFormat, GLsizei width, GLsizei height, bool fixedSampleLocations, bool isSRGB )
{
	GLint finalFormat = GL_ToSRGB( internalFormat, isSRGB );

	glTexImage2DMultisample( target, samples, finalFormat, width, height, fixedSampleLocations );
}

void GL_TexImage3D( GLenum target, GLint level, GLint internalFormat, GLsizei width, GLsizei height, GLsizei depth, GLint border, GLenum format, GLenum type, const void *data, bool isSRGB )
{
	GLint finalFormat = GL_ToSRGB( internalFormat, isSRGB );

	glTexImage3D( target, level, finalFormat, width, height, depth, border, format, type, data );
}

void GL_CompressedTexImage2D( GLenum target, GLint level, GLenum internalFormat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const void *data, bool isSRGB )
{
	GLint finalFormat = GL_ToSRGB( internalFormat, isSRGB );

	glCompressedTexImage2D( target, level, finalFormat, width, height, border, imageSize, data );
}

void GL_CompressedTexSubImage3D( GLenum target, GLint level, GLint xOffset, GLint yOffset, GLint zOffset, GLsizei width, GLsizei height, GLsizei depth, GLenum internalFormat, GLsizei size, const void *data, bool isSRGB )
{
	GLint finalFormat = GL_ToSRGB( internalFormat, isSRGB );

	glCompressedTexSubImage3D( target, level, xOffset, yOffset, zOffset, width, height, depth, finalFormat, size, data );
}

/*
================
RB_Hyperspace

A player has predicted a teleport, but hasn't arrived yet
================
*/
static void RB_Hyperspace()
{
	float c;

	if ( !backEnd.isHyperspace )
	{
		// do initialization shit
	}

	c = ( backEnd.refdef.time & 255 ) / 255.0f;
	GL_ClearColor( c, c, c, 1 );
	glClear( GL_COLOR_BUFFER_BIT );

	backEnd.isHyperspace = true;
}

static void SetViewportAndScissor()
{
	float	mat[16], scale;
	vec4_t	q, c;

	MatrixCopy( backEnd.viewParms.projectionMatrix, mat );
	if( backEnd.viewParms.portalLevel > 0 )
	{
		VectorCopy(backEnd.viewParms.portalFrustum[FRUSTUM_NEAR].normal, c);
		c[3] = backEnd.viewParms.portalFrustum[FRUSTUM_NEAR].dist;

		// Lengyel, Eric. "Modifying the Projection Matrix to Perform Oblique Near-plane Clipping".
		// Terathon Software 3D Graphics Library, 2004. http://www.terathon.com/code/oblique.html
		q[0] = (c[0] < 0.0f ? -1.0f : 1.0f) / mat[0];
		q[1] = (c[1] < 0.0f ? -1.0f : 1.0f) / mat[5];
		q[2] = -1.0f;
		q[3] = (1.0f + mat[10]) / mat[14];

		scale = 2.0f / (DotProduct( c, q ) + c[3] * q[3]);
		mat[2]  = c[0] * scale;
		mat[6]  = c[1] * scale;
		mat[10] = c[2] * scale + 1.0f;
		mat[14] = c[3] * scale;
	}

	GL_LoadProjectionMatrix( mat );

	// set the window clipping
	GL_Viewport( backEnd.viewParms.viewportX, backEnd.viewParms.viewportY,
	             backEnd.viewParms.viewportWidth, backEnd.viewParms.viewportHeight );

	GL_Scissor( backEnd.viewParms.scissorX, backEnd.viewParms.scissorY,
	            backEnd.viewParms.scissorWidth, backEnd.viewParms.scissorHeight);
}

/*
================
RB_SetGL2D
================
*/
static void RB_SetGL2D()
{
	matrix_t proj;

	GLIMP_LOGCOMMENT( "--- RB_SetGL2D ---" );

	// disable offscreen rendering
	R_BindNullFBO();

	backEnd.projection2D = true;

	// set 2D virtual screen size
	GL_Viewport( 0, 0, windowConfig.vidWidth, windowConfig.vidHeight );
	GL_Scissor( 0, 0, windowConfig.vidWidth, windowConfig.vidHeight );

	MatrixOrthogonalProjection( proj, 0, windowConfig.vidWidth, windowConfig.vidHeight, 0, 0, 1 );
	// zero the z coordinate so it's never near/far clipped
	proj[ 2 ] = proj[ 6 ] = proj[ 10 ] = proj[ 14 ] = 0;

	GL_LoadProjectionMatrix( proj );
	GL_LoadModelViewMatrix( matrixIdentity );

	GL_Cull( cullType_t::CT_TWO_SIDED );

	// set time for 2D shaders
	backEnd.refdef.time = ri.Milliseconds();
	backEnd.refdef.floatTime =float(double(backEnd.refdef.time) * 0.001);
}

// used as bitfield
enum renderDrawSurfaces_e
{
  DRAWSURFACES_WORLD         = 1 << 0,
  DRAWSURFACES_FAR_ENTITIES  = 1 << 1,
  DRAWSURFACES_NEAR_ENTITIES = 1 << 2,
  DRAWSURFACES_ALL_FAR       = DRAWSURFACES_WORLD | DRAWSURFACES_FAR_ENTITIES,
  DRAWSURFACES_ALL_ENTITIES  = DRAWSURFACES_FAR_ENTITIES | DRAWSURFACES_NEAR_ENTITIES,
  DRAWSURFACES_ALL           = DRAWSURFACES_WORLD | DRAWSURFACES_ALL_ENTITIES
};

// When rendering a surface, the geometry generally goes through a three-stage pipeline:
// (1) Surface function (from rb_surfaceTable). This function generates the triangles, either by
//     explicitly writing them out, or by indicating a range from a static VBO/IBO.
// (2) Stage iterator function. Loops over the stages of a q3shader (if applicable), and sets up
//     some drawing parameters, in particular tess.svars, for each one. Responsible for updating
//     the non-static VBO (tess.verts) if it is used.
// (3) Render function. Feeds parameters to the GLSL shader and executes it with Tess_DrawElements.
//
// Function (1) is chosen based on the type of surface. (2) is chosen at the top level. (3) is
// chosen by (2).
//
// Batches of triangles from multiple calls to (1) may be merged together if everything is
// compatible between them. Draw surf sorting is an attempt to make this happen more often. But
// if there is not enough room in the buffers, an immediate call to (2) may be needed. Each batch
// of triangles may be rendered multiple times as (2) iterates shader stages.
//
// Note that portal recursion is done in the frontend when adding draw surfaces, not here.
static void RB_RenderDrawSurfaces( shaderSort_t fromSort, shaderSort_t toSort,
				   renderDrawSurfaces_e drawSurfFilter )
{
	trRefEntity_t *entity, *oldEntity;
	shader_t      *shader, *oldShader;
	int           lightmapNum, oldLightmapNum;
	bool          bspSurface;
	bool      depthRange, oldDepthRange;
	int           i;
	drawSurf_t    *drawSurf;
	int           lastSurf;

	GLIMP_LOGCOMMENT( "--- RB_RenderDrawSurfaces ---" );

	// draw everything
	oldEntity = nullptr;
	oldShader = nullptr;
	oldLightmapNum = -1;
	oldDepthRange = false;
	depthRange = false;

	lastSurf = backEnd.viewParms.firstDrawSurf[ Util::ordinal(toSort) + 1 ];
	for ( i = backEnd.viewParms.firstDrawSurf[ Util::ordinal(fromSort) ]; i < lastSurf; i++ )
	{
		drawSurf = &backEnd.viewParms.drawSurfs[ i ];

		// FIXME: investigate why this happens.
		if( drawSurf->surface == nullptr )
		{
			continue;
		}

		// update locals
		entity = drawSurf->entity;
		shader = drawSurf->shader;
		lightmapNum = drawSurf->lightmapNum();
		bspSurface = drawSurf->bspSurface;

		if( entity == &tr.worldEntity ) {
			if( !( drawSurfFilter & DRAWSURFACES_WORLD ) )
				continue;
		} else if( !( entity->e.renderfx & RF_DEPTHHACK ) ) {
			if( !( drawSurfFilter & DRAWSURFACES_FAR_ENTITIES ) )
				continue;
		} else {
			if( !( drawSurfFilter & DRAWSURFACES_NEAR_ENTITIES ) )
				continue;
		}

		if ( entity == oldEntity && shader == oldShader && lightmapNum == oldLightmapNum )
		{
			// fast path, same as previous sort
			rb_surfaceTable[Util::ordinal(*drawSurf->surface)](drawSurf->surface );
			continue;
		}

		// change the tess parameters if needed
		// an "entityMergable" shader is a shader that can have surfaces from separate
		// entities merged into a single batch, like smoke and blood puff sprites
		if ( shader != oldShader || lightmapNum != oldLightmapNum || ( entity != oldEntity && !shader->entityMergable ) )
		{
			if ( oldShader != nullptr )
			{
				Tess_End();
			}

			Tess_Begin( Tess_StageIteratorColor, shader, false, lightmapNum, bspSurface );

			oldShader = shader;
			oldLightmapNum = lightmapNum;
		}

		// change the modelview matrix if needed
		if ( entity != oldEntity )
		{
			depthRange = false;

			if ( entity != &tr.worldEntity )
			{
				backEnd.currentEntity = entity;

				// set up the transformation matrix
				R_RotateEntityForViewParms( backEnd.currentEntity, &backEnd.viewParms, &backEnd.orientation );

				if ( backEnd.currentEntity->e.renderfx & RF_DEPTHHACK )
				{
					// hack the depth range to prevent view model from poking into walls
					depthRange = true;
				}
			}
			else
			{
				backEnd.currentEntity = &tr.worldEntity;
				backEnd.orientation = backEnd.viewParms.world;
			}

			GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );

			// change depthrange if needed
			if ( oldDepthRange != depthRange )
			{
				if ( depthRange )
				{
					glDepthRange( 0, 0.3 );
				}
				else
				{
					glDepthRange( 0, 1 );
				}

				oldDepthRange = depthRange;
			}

			oldEntity = entity;
		}

		// add the triangles for this surface
		rb_surfaceTable[Util::ordinal(*drawSurf->surface)](drawSurf->surface );
	}

	// draw the contents of the last shader batch
	if ( oldShader != nullptr )
	{
		Tess_End();
	}

	// go back to the world modelview matrix
	GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );

	if ( depthRange )
	{
		glDepthRange( 0, 1 );
	}

	GL_CheckErrors();
}

/*
=============
RB_RunVisTests
=============
*/
void RB_RunVisTests( )
{
	int i;

	// finish any 2D drawing if needed
	Tess_End();

	for ( i = 0; i < backEnd.refdef.numVisTests; i++ )
	{
		vec3_t           diff;
		vec3_t           center, left, up;
		visTestResult_t  *test = &backEnd.refdef.visTests[ i ];
		visTestQueries_t *testState = &backEnd.visTestQueries[ test->visTestHandle - 1 ];

		if ( testState->running && !test->discardExisting )
		{
			GLint  available;
			GLuint result, resultRef;

			glGetQueryObjectiv( testState->hQuery,
					    GL_QUERY_RESULT_AVAILABLE,
					    &available );
			if( !available )
			{
				continue;
			}

			glGetQueryObjectiv( testState->hQueryRef,
					    GL_QUERY_RESULT_AVAILABLE,
					    &available );
			if ( !available )
			{
				continue;
			}

			glGetQueryObjectuiv( testState->hQueryRef, GL_QUERY_RESULT,
					     &resultRef );
			glGetQueryObjectuiv( testState->hQuery, GL_QUERY_RESULT,
					     &result );

			if ( resultRef > 0 )
			{
				test->lastResult = (float)result / (float)resultRef;
			}
			else
			{
				test->lastResult = 0.0f;
			}

			testState->running = false;
		}

		Tess_MapVBOs( false );
		VectorSubtract( backEnd.orientation.viewOrigin,
				test->position, diff );
		VectorNormalize( diff );
		VectorMA( test->position, test->depthAdjust, diff, center );

		VectorScale( backEnd.viewParms.orientation.axis[ 1 ],
			     test->area, left );
		VectorScale( backEnd.viewParms.orientation.axis[ 2 ],
			     test->area, up );

		tess.verts[ 0 ].xyz[ 0 ] = center[ 0 ] + left[ 0 ] + up[ 0 ];
		tess.verts[ 0 ].xyz[ 1 ] = center[ 1 ] + left[ 1 ] + up[ 1 ];
		tess.verts[ 0 ].xyz[ 2 ] = center[ 2 ] + left[ 2 ] + up[ 2 ];
		tess.verts[ 1 ].xyz[ 0 ] = center[ 0 ] - left[ 0 ] + up[ 0 ];
		tess.verts[ 1 ].xyz[ 1 ] = center[ 1 ] - left[ 1 ] + up[ 1 ];
		tess.verts[ 1 ].xyz[ 2 ] = center[ 2 ] - left[ 2 ] + up[ 2 ];
		tess.verts[ 2 ].xyz[ 0 ] = center[ 0 ] - left[ 0 ] - up[ 0 ];
		tess.verts[ 2 ].xyz[ 1 ] = center[ 1 ] - left[ 1 ] - up[ 1 ];
		tess.verts[ 2 ].xyz[ 2 ] = center[ 2 ] - left[ 2 ] - up[ 2 ];
		tess.verts[ 3 ].xyz[ 0 ] = center[ 0 ] + left[ 0 ] - up[ 0 ];
		tess.verts[ 3 ].xyz[ 1 ] = center[ 1 ] + left[ 1 ] - up[ 1 ];
		tess.verts[ 3 ].xyz[ 2 ] = center[ 2 ] + left[ 2 ] - up[ 2 ];
		tess.numVertexes = 4;

		tess.indexes[ 0 ] = 0;
		tess.indexes[ 1 ] = 1;
		tess.indexes[ 2 ] = 2;
		tess.indexes[ 3 ] = 0;
		tess.indexes[ 4 ] = 2;
		tess.indexes[ 5 ] = 3;
		tess.numIndexes = 6;

		Tess_UpdateVBOs( );
		GL_VertexAttribsState( ATTR_POSITION );

		gl_genericShader->SetVertexSkinning( false );
		gl_genericShader->SetVertexAnimation( false );
		gl_genericShader->SetTCGenEnvironment( false );
		gl_genericShader->SetTCGenLightmap( false );
		gl_genericShader->SetDepthFade( false );
		gl_genericShader->SetDeform( 0 );
		gl_genericShader->BindProgram();

		gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
		SetUniform_Color( gl_genericShader, Color::White );

		SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_CONST, alphaGen_t::AGEN_CONST );
		gl_genericShader->SetUniform_ModelMatrix( backEnd.orientation.transformMatrix );
		gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.whiteImage )
		);
		gl_genericShader->SetUniform_TextureMatrix( tess.svars.texMatrices[ TB_COLORMAP ] );

		GL_State( GLS_DEPTHTEST_DISABLE | GLS_COLORMASK_BITS );
		glBeginQuery( GL_SAMPLES_PASSED, testState->hQueryRef );
		Tess_DrawElements();
		glEndQuery( GL_SAMPLES_PASSED );

		GL_State( GLS_COLORMASK_BITS );
		glBeginQuery( GL_SAMPLES_PASSED, testState->hQuery );
		Tess_DrawElements();
		glEndQuery( GL_SAMPLES_PASSED );

		Tess_Clear();
		testState->running = true;
	}
}

void RB_PrepareForSamplingDepthMap()
{
	if ( glConfig.usingReadonlyDepth )
	{
		return;
	}

	if ( !glConfig.textureBarrierAvailable )
	{
		return;
	}

	if ( !backEnd.dirtyDepthBuffer )
	{
		return;
	}

	// Flush depth buffer to make sure it is available for reading in the depth fade
	// GLSL - prevents https://github.com/DaemonEngine/Daemon/issues/1676
	glTextureBarrier();

	backEnd.dirtyDepthBuffer = false;
}

static void RenderDepthTiles()
{
	GL_State( GLS_DEPTHTEST_DISABLE );
	GL_Cull( CT_TWO_SIDED );

	if ( !r_depthShaders.Get() )
	{
		// put max range so depth-based planes will always pass in lighttile
		// setting to 99999 worked on my machines but is technically not allowed by the spec
		// ARB_color_buffer_float lets you set values outside of [0, 1] but we use
		// a different extension ARB_texture_float to get float color buffer
		R_BindFBO( tr.depthtile2FBO );
		glClearColor( /*max*/ 99999.f, /*min*/ 0.0f, 0.0f, 0.0f );
		glClear( GL_COLOR_BUFFER_BIT );
		return;
	}

	if ( glConfig.usingBindlessTextures )
	{
		RB_PrepareForSamplingDepthMap();
	}
	
	TransitionMSAAToMain( GL_DEPTH_BUFFER_BIT );

	// 1st step
	R_BindFBO( tr.depthtile1FBO );
	GL_Viewport( 0, 0, tr.depthtile1FBO->width, tr.depthtile1FBO->height );
	GL_Scissor( 0, 0, tr.depthtile1FBO->width, tr.depthtile1FBO->height );
	gl_depthtile1Shader->BindProgram();

	vec3_t zParams;
	zParams[ 0 ] = 2.0f * tanf( DEG2RAD( backEnd.refdef.fov_x * 0.5f) ) / windowConfig.vidWidth;
	zParams[ 1 ] = 2.0f * tanf( DEG2RAD( backEnd.refdef.fov_y * 0.5f) ) / windowConfig.vidHeight;
	zParams[ 2 ] = backEnd.viewParms.zFar;

	gl_depthtile1Shader->SetUniform_zFar( zParams );
	gl_depthtile1Shader->SetUniform_DepthMapBindless(
		GL_BindToTMU( 0, tr.currentDepthImage ) 
	);

	matrix_t ortho;
	GL_PushMatrix();
	MatrixOrthogonalProjection( ortho, backEnd.viewParms.viewportX,
		backEnd.viewParms.viewportX + backEnd.viewParms.viewportWidth,
		backEnd.viewParms.viewportY,
		backEnd.viewParms.viewportY + backEnd.viewParms.viewportHeight, -99999, 99999 );
	GL_LoadProjectionMatrix( ortho );

	Tess_InstantQuad( *gl_depthtile1Shader,
	                  backEnd.viewParms.viewportX, backEnd.viewParms.viewportY,
	                  backEnd.viewParms.viewportWidth, backEnd.viewParms.viewportHeight );

	GL_PopMatrix();

	// 2nd step
	R_BindFBO( tr.depthtile2FBO );

	GL_Viewport( 0, 0, tr.depthtile2FBO->width, tr.depthtile2FBO->height );
	GL_Scissor( 0, 0, tr.depthtile2FBO->width, tr.depthtile2FBO->height );
	gl_depthtile2Shader->BindProgram();

	gl_depthtile2Shader->SetUniform_DepthTile1Bindless(
		GL_BindToTMU( 0, tr.depthtile1RenderImage )
	);

	Tess_InstantScreenSpaceQuad();
}

void RB_RenderPostDepthLightTile()
{
	if ( !glConfig.realtimeLighting )
	{
		return;
	}

	if ( !backEnd.refdef.numLights ) {
		return;
	}

	if ( ( backEnd.refdef.rdflags & RDF_NOWORLDMODEL ) )
	{
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_RenderPostDepthLightTile ---" );

	RenderDepthTiles();

	vec3_t projToViewParams;
	projToViewParams[0] = tanf(DEG2RAD(backEnd.refdef.fov_x * 0.5f)) * backEnd.viewParms.zFar;
	projToViewParams[1] = tanf(DEG2RAD(backEnd.refdef.fov_y * 0.5f)) * backEnd.viewParms.zFar;
	projToViewParams[2] = backEnd.viewParms.zFar;

	// render lights
	R_BindFBO( tr.lighttileFBO );
	gl_lighttileShader->BindProgram();
	gl_lighttileShader->SetUniform_ModelMatrix( backEnd.viewParms.world.modelViewMatrix );
	gl_lighttileShader->SetUniform_numLights( backEnd.refdef.numLights );
	gl_lighttileShader->SetUniform_zFar( projToViewParams );

	gl_lighttileShader->SetUniformBlock_Lights( tr.dlightUBO );

	gl_lighttileShader->SetUniform_DepthTile2Bindless(
		GL_BindToTMU( 0, tr.depthtile2RenderImage )
	);

	R_BindVBO( tr.lighttileVBO );

	for( int layer = 0; layer < glConfig.realtimeLightLayers; layer++ ) {
		R_AttachFBOTexture3D( tr.lighttileRenderImage->texnum, 0, layer );
		gl_lighttileShader->SetUniform_lightLayer( layer );

		GL_Viewport( 0, 0, tr.lighttileRenderImage->width, tr.lighttileRenderImage->height );
		tess.numIndexes = 0;
		tess.numVertexes = tr.lighttileVBO->vertexesNum;

		GL_VertexAttribsState( ATTR_POSITION | ATTR_TEXCOORD );
		if( !glConfig.glCoreProfile )
			glEnable( GL_POINT_SPRITE );
		glEnable( GL_PROGRAM_POINT_SIZE );

		// Radeon R300 small ALU is known to fail on this.
		Tess_DrawArrays( GL_POINTS );

		glDisable( GL_PROGRAM_POINT_SIZE );
		if( !glConfig.glCoreProfile )
			glDisable( GL_POINT_SPRITE );
	}

	Tess_Clear();

	// back to main image
	BindMSAAOrMainFBO();

	GL_Viewport( backEnd.viewParms.viewportX, backEnd.viewParms.viewportY,
		     backEnd.viewParms.viewportWidth, backEnd.viewParms.viewportHeight );
	GL_Scissor( backEnd.viewParms.scissorX, backEnd.viewParms.scissorY,
		    backEnd.viewParms.scissorWidth, backEnd.viewParms.scissorHeight );

	GL_CheckErrors();
}

void RB_RenderBloom()
{
	if ( ( backEnd.refdef.rdflags & ( RDF_NOWORLDMODEL | RDF_NOBLOOM ) )
		|| !glConfig.bloom || backEnd.viewParms.portalLevel > 0 ) {
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_RenderBloom ---" );

	{
		GL_State( GLS_DEPTHTEST_DISABLE );
		GL_Cull( cullType_t::CT_TWO_SIDED );

		// render contrast downscaled to 1/4th of the screen
		gl_contrastShader->BindProgram();

		gl_contrastShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.currentRenderImage[backEnd.currentMainFBO] )
		);

		TransitionMSAAToMain( GL_COLOR_BUFFER_BIT );

		R_BindFBO( tr.contrastRenderFBO );
		GL_ClearColor( 0.0f, 0.0f, 0.0f, 1.0f );
		glClear( GL_COLOR_BUFFER_BIT );

		Tess_InstantScreenSpaceQuad();

		// render bloom in multiple passes
		GL_ClearColor( 0.0f, 0.0f, 0.0f, 1.0f );
		GL_State( GLS_DEPTHTEST_DISABLE );

		vec2_t texScale;
		texScale[0] = 1.0f / tr.bloomRenderFBO[0]->width;
		texScale[1] = 1.0f / tr.bloomRenderFBO[0]->height;

		gl_blurShader->BindProgram();

		gl_blurShader->SetUniform_DeformMagnitude( r_bloomBlur.Get() );
		gl_blurShader->SetUniform_TexScale( texScale );

		gl_blurShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.contrastRenderFBOImage )
		);

		gl_blurShader->SetUniform_Horizontal( true );

		int flip = 0;
		for ( int i = 0; i < 2; i++ ) {
			for ( int j = 0; j < r_bloomPasses.Get(); j++ ) {
				R_BindFBO( tr.bloomRenderFBO[flip] );
				glClear( GL_COLOR_BUFFER_BIT );

				Tess_InstantScreenSpaceQuad();

				gl_blurShader->SetUniform_ColorMapBindless(
					GL_BindToTMU( 0, tr.bloomRenderFBOImage[flip] )
				);

				flip ^= 1;
			}

			gl_blurShader->SetUniform_Horizontal( false );
		}

		R_BindFBO( tr.mainFBO[backEnd.currentMainFBO] );

		gl_screenShader->BindProgram();
		GL_State( GLS_DEPTHTEST_DISABLE | GLS_SRCBLEND_ONE | GLS_DSTBLEND_ONE );
		glVertexAttrib4fv( ATTR_INDEX_COLOR, Color::White.ToArray() );

		gl_screenShader->SetUniform_CurrentMapBindless( GL_BindToTMU( 0, tr.bloomRenderFBOImage[flip ^ 1] ) );

		GL_PushMatrix();

		matrix_t ortho;
		MatrixOrthogonalProjection( ortho, 0, tr.bloomRenderFBO[0]->width, 0, tr.bloomRenderFBO[0]->height, -99999, 99999 );
		GL_LoadProjectionMatrix( ortho );

		Tess_InstantQuad( *gl_screenShader,
			backEnd.viewParms.viewportX, backEnd.viewParms.viewportY,
			backEnd.viewParms.viewportWidth, backEnd.viewParms.viewportHeight );

		GL_PopMatrix();
	}

	TransitionMainToMSAA( GL_COLOR_BUFFER_BIT );

	GL_CheckErrors();
}

void RB_RenderMotionBlur()
{
	if ( !glConfig.motionBlur || ( backEnd.refdef.rdflags & RDF_NOWORLDMODEL )
		|| backEnd.viewParms.portalLevel > 0 )
	{
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_RenderMotionBlur ---" );

	RB_PrepareForSamplingDepthMap();

	GL_State( GLS_DEPTHTEST_DISABLE );
	GL_Cull( cullType_t::CT_TWO_SIDED );

	gl_motionblurShader->BindProgram();

	TransitionMSAAToMain( GL_COLOR_BUFFER_BIT );

	// Swap main FBOs
	gl_motionblurShader->SetUniform_ColorMapBindless(
		GL_BindToTMU( 0, tr.currentRenderImage[backEnd.currentMainFBO] )
	);
	backEnd.currentMainFBO = 1 - backEnd.currentMainFBO;
	R_BindFBO( tr.mainFBO[ backEnd.currentMainFBO ] );

	gl_motionblurShader->SetUniform_blurVec(tr.refdef.blurVec);

	gl_motionblurShader->SetUniform_DepthMapBindless(
		GL_BindToTMU( 1, tr.depthSamplerImage )
	);

	Tess_InstantScreenSpaceQuad();

	TransitionMainToMSAA( GL_COLOR_BUFFER_BIT );

	GL_CheckErrors();
}

void RB_RenderSSAO()
{
	if ( !glConfig.SSAO )
	{
		return;
	}

	if ( ( backEnd.refdef.rdflags & RDF_NOWORLDMODEL ) ||
	     backEnd.viewParms.portalLevel > 0 )
	{
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_RenderSSAO ---" );

	RB_PrepareForSamplingDepthMap();

	GL_State( GLS_DEPTHTEST_DISABLE | GLS_SRCBLEND_DST_COLOR | GLS_DSTBLEND_ZERO );
	GL_Cull( cullType_t::CT_TWO_SIDED );

	if ( glConfig.SSAO && r_SSAO.Get() == Util::ordinal( ssaoMode::SHOW ) ) {
		// clear the screen to show only SSAO
		GL_ClearColor( 1.0, 1.0, 1.0, 1.0 );
		glClear( GL_COLOR_BUFFER_BIT );
	}

	gl_ssaoShader->BindProgram();

	vec3_t zParams;
	zParams[ 0 ] = 2.0f * tanf( DEG2RAD( backEnd.refdef.fov_x * 0.5f ) ) / windowConfig.vidWidth;
	zParams[ 1 ] = 2.0f * tanf( DEG2RAD( backEnd.refdef.fov_y * 0.5f ) ) / windowConfig.vidHeight;
	zParams[ 2 ] = backEnd.viewParms.zFar;

	gl_ssaoShader->SetUniform_zFar( zParams );

	vec3_t unprojectionParams;
	unprojectionParams[ 0 ] = -r_znear->value * zParams[ 2 ];
	unprojectionParams[ 1 ] = 2.0 * ( zParams[ 2 ] - r_znear->value );
	unprojectionParams[ 2 ] = 2.0 * zParams[ 2 ] - r_znear->value;

	gl_ssaoShader->SetUniform_UnprojectionParams( unprojectionParams );

	gl_ssaoShader->SetUniform_DepthMapBindless(
		GL_BindToTMU( 0, tr.depthSamplerImage )
	);

	Tess_InstantScreenSpaceQuad();

	GL_CheckErrors();
}

void RB_FXAA()
{
	if ( !glConfig.FXAA || !gl_fxaaShader )
	{
		return;
	}

	if ( ( backEnd.refdef.rdflags & RDF_NOWORLDMODEL ) || backEnd.viewParms.portalLevel )
	{
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_FXAA ---" );

	GL_State( GLS_DEPTHTEST_DISABLE );
	GL_Cull( cullType_t::CT_TWO_SIDED );

	// set the shader parameters
	gl_fxaaShader->BindProgram();

	gl_fxaaShader->SetUniform_ColorMapBindless(
		GL_BindToTMU( 0, tr.currentRenderImage[backEnd.currentMainFBO] )
	);

	// FXAA expects GL_LINEAR for the sampling to work.
	GLuint64 handle = 0;

	if ( glConfig.usingBindlessTextures )
	{
		// Set a handler.
		GLuint texture = tr.currentRenderImage[backEnd.currentMainFBO]->texnum;
		handle = glGetTextureSamplerHandleARB( texture, tr.linearSampler );
		glMakeTextureHandleResidentARB( handle );
		GLuint program = gl_fxaaShader->GetProgram()->id;
		GLint location = glGetUniformLocation( program, "u_ColorMap_linear" );
		glUniformHandleui64ARB( location, handle );
	}
	else
	{
		// Bind a sampler.
		glBindSampler( 0, tr.linearSampler );
	}

	// This shader is run last, so let it render to screen.
	R_BindNullFBO();

	Tess_InstantScreenSpaceQuad();

	// Make sure we didn't break other effects expecting GL_NEAREST.
	if ( glConfig.usingBindlessTextures )
	{
		// Unset the handler.
		glMakeTextureHandleNonResidentARB( handle );
	}
	else
	{
		// Unbind the sampler.
		glBindSampler( 0, 0 );
	}

	GL_CheckErrors();
}

static void ComputeTonemapParams( const float contrast, const float highlightsCompressionSpeed,
	const float HDRMax,
	const float darkAreaPointHDR, const float darkAreaPointLDR,
	float& shoulderClip, float& highlightsCompression ) {
	// Lottes 2016, "Advanced Techniques and Optimization of HDR Color Pipelines"
	/* a: contrast
	d: highlightsCompressionSpeed
	b: shoulderClip
	c: highlightsCompression
	hdrMax: HDRMax
	midIn: darkAreaPointHDR
	midOut: darkAreaPointLDR */

	shoulderClip =
		( -powf( darkAreaPointHDR, contrast ) + powf( HDRMax, contrast ) * darkAreaPointLDR )
		/
		( ( powf( HDRMax, contrast * highlightsCompressionSpeed )
			- powf( darkAreaPointHDR, contrast * highlightsCompressionSpeed )
		) * darkAreaPointLDR );
	highlightsCompression =
		( powf( HDRMax, contrast * highlightsCompressionSpeed ) * powf( darkAreaPointHDR, contrast )
			- powf( HDRMax, contrast ) * powf( darkAreaPointHDR, contrast * highlightsCompressionSpeed ) * darkAreaPointLDR
		)
		/
		( ( powf( HDRMax, contrast * highlightsCompressionSpeed )
			- powf( darkAreaPointHDR, contrast * highlightsCompressionSpeed )
		) * darkAreaPointLDR );
}

void RB_CameraPostFX() {
	if ( ( backEnd.refdef.rdflags & RDF_NOWORLDMODEL ) ||
	     backEnd.viewParms.portalLevel > 0 ) {
		return;
	}

	GLIMP_LOGCOMMENT( "--- RB_CameraPostFX ---" );

	GL_State( GLS_DEPTHTEST_DISABLE );
	GL_Cull( cullType_t::CT_TWO_SIDED );

	// enable shader, set arrays
	gl_cameraEffectsShader->BindProgram();

	gl_cameraEffectsShader->SetUniform_GlobalLightFactor( 1.0f / tr.identityLight );
	gl_cameraEffectsShader->SetUniform_ColorModulate( backEnd.viewParms.gradingWeights );

	gl_cameraEffectsShader->SetUniform_InverseGamma( 1.0 / r_gamma->value );

	gl_cameraEffectsShader->SetUniform_SRGB( tr.worldLinearizeTexture );
	gl_cameraEffectsShader->SetUniform_Exposure( r_exposure.Get() );

	const bool tonemap = r_toneMapping.Get() && r_highPrecisionRendering.Get() && glConfig.textureFloatAvailable;
	if ( tonemap ) {
		vec4_t tonemapParms { r_toneMappingContrast.Get(), r_toneMappingHighlightsCompressionSpeed.Get() };
		ComputeTonemapParams( tonemapParms[0], tonemapParms[1], r_toneMappingHDRMax.Get(),
			r_toneMappingDarkAreaPointHDR.Get(), r_toneMappingDarkAreaPointLDR.Get(), tonemapParms[2], tonemapParms[3] );
		gl_cameraEffectsShader->SetUniform_TonemapParms( tonemapParms );
	}
	gl_cameraEffectsShader->SetUniform_Tonemap( tonemap );

	gl_cameraEffectsShader->SetUniform_CurrentMapBindless(
		GL_BindToTMU( 0, tr.currentRenderImage[backEnd.currentMainFBO] ) 
	);

	if ( r_FXAA.Get() && gl_fxaaShader )
	{
		// Swap main FBOs.
		backEnd.currentMainFBO = 1 - backEnd.currentMainFBO;
		R_BindFBO( tr.mainFBO[ backEnd.currentMainFBO ] );
	}
	else
	{
		// Without FXAA this shader is run last, so let it render to screen.
		R_BindNullFBO();
	}

	if ( glConfig.colorGrading ) {
		gl_cameraEffectsShader->SetUniform_ColorMap3DBindless( GL_BindToTMU( 3, tr.colorGradeImage ) );
	}

	Tess_InstantScreenSpaceQuad();

	GL_CheckErrors();
}

static void RB_RenderDebugUtils()
{
	GLIMP_LOGCOMMENT( "--- RB_RenderDebugUtils ---" );

	if ( r_showEntityBounds.Get() )
	{
		trRefEntity_t *ent;
		int           i;
		static const vec3_t mins = { -1, -1, -1 };
		static const vec3_t maxs = { 1, 1, 1 };

		gl_genericShader->SetVertexSkinning( false );
		gl_genericShader->SetVertexAnimation( false );
		gl_genericShader->SetTCGenEnvironment( false );
		gl_genericShader->SetTCGenLightmap( false );
		gl_genericShader->SetDepthFade( false );
		gl_genericShader->SetDeform( 0 );
		gl_genericShader->BindProgram();

		if ( r_showEntityBounds.Get() == 2 )
		{
			GL_State( GLS_SRCBLEND_SRC_ALPHA | GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA );
			glEnable( GL_POLYGON_OFFSET_FILL );
			GL_PolygonOffset( r_offsetFactor->value, r_offsetUnits->value );
		}
		else
		{
			GL_State( GLS_POLYMODE_LINE | GLS_DEPTHTEST_DISABLE );
		}

		GL_Cull( cullType_t::CT_TWO_SIDED );

		// set uniforms
		gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
		SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
		SetUniform_Color( gl_genericShader, Color::Color(0, 0, 0, 0) );

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.whiteImage )
		);
		gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

		ent = backEnd.refdef.entities;

		for ( i = 0; i < backEnd.refdef.numEntities; i++, ent++ )
		{
			if ( ent->e.reType != refEntityType_t::RT_MODEL )
			{
				continue;
			}

			if ( ( ent->e.renderfx & RF_THIRD_PERSON ) &&
			     backEnd.viewParms.portalLevel == 0 )
			{
				continue;
			}

			// set up the transformation matrix
			R_RotateEntityForViewParms( ent, &backEnd.viewParms, &backEnd.orientation );
			GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );
			gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

			Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

			if ( r_showEntityBounds.Get() == 2)
			{
				Tess_AddCube( vec3_origin, ent->localBounds[ 0 ], ent->localBounds[ 1 ], Color::Color(0, 0, 0.5, 0.4) );
			}
			else
			{
				Tess_AddCube( vec3_origin, ent->localBounds[ 0 ], ent->localBounds[ 1 ], Color::Blue );
				Tess_AddCube( vec3_origin, mins, maxs,Color::White );
			}

			Tess_End();
		}

		// go back to the world modelview matrix
		backEnd.orientation = backEnd.viewParms.world;
		GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );
		glDisable( GL_POLYGON_OFFSET_FILL );
	}

	if ( r_showSkeleton->integer )
	{
		int                  i, j, k, parentIndex;
		trRefEntity_t        *ent;
		vec3_t               offset;
		vec3_t               diff, tmp, tmp2, tmp3;
		vec_t                length;
		vec4_t               tetraVerts[ 4 ];
		static refSkeleton_t skeleton;
		refSkeleton_t        *skel;

		gl_genericShader->SetVertexSkinning( false );
		gl_genericShader->SetVertexAnimation( false );
		gl_genericShader->SetTCGenEnvironment( false );
		gl_genericShader->SetTCGenLightmap( false );
		gl_genericShader->SetDepthFade( false );
		gl_genericShader->SetDeform( 0 );
		gl_genericShader->BindProgram();

		GL_Cull( cullType_t::CT_TWO_SIDED );

		// set uniforms
		gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
		SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
		SetUniform_Color( gl_genericShader, Color::Black );

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.whiteImage )
		);

		gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

		ent = backEnd.refdef.entities;

		for ( i = 0; i < backEnd.refdef.numEntities; i++, ent++ )
		{
			if ( ( ent->e.renderfx & RF_THIRD_PERSON && backEnd.viewParms.portalLevel == 0 ) ||
			     ( ent->e.renderfx & RF_FIRST_PERSON && backEnd.viewParms.portalLevel != 0 ) )
			{
				continue;
			}

			// set up the transformation matrix
			R_RotateEntityForViewParms( ent, &backEnd.viewParms, &backEnd.orientation );
			GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );
			gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

			skel = nullptr;

			if ( ent->e.skeleton.type == refSkeletonType_t::SK_ABSOLUTE )
			{
				skel = &ent->e.skeleton;
			}
			else
			{
				model_t   *model;
				refBone_t *bone;

				model = R_GetModelByHandle( ent->e.hModel );

				if ( model )
				{
					switch ( model->type )
					{
						case modtype_t::MOD_MD5:
							{
								// copy absolute bones
								skeleton.numBones = model->md5->numBones;

								for ( j = 0, bone = &skeleton.bones[ 0 ]; j < skeleton.numBones; j++, bone++ )
								{
#if defined( REFBONE_NAMES )
									Q_strncpyz( bone->name, model->md5->bones[ j ].name, sizeof( bone->name ) );
#endif

									bone->parentIndex = model->md5->bones[ j ].parentIndex;
									TransInitRotationQuat( model->md5->bones[ j ].rotation, &bone->t );
									TransAddTranslation( model->md5->bones[ j ].origin, &bone->t );
								}

								skel = &skeleton;
								break;
							}

						default:
							break;
					}
				}
			}

			if ( skel )
			{
				static vec3_t worldOrigins[ MAX_BONES ];

				GL_State( GLS_POLYMODE_LINE | GLS_DEPTHTEST_DISABLE );
				Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

				for ( j = 0; j < skel->numBones; j++ )
				{
					parentIndex = skel->bones[ j ].parentIndex;
					vec3_t origin;

					if ( parentIndex < 0 )
					{
						VectorClear( origin );
					}
					else
					{
						VectorCopy( skel->bones[ parentIndex ].t.trans, origin );
					}

					VectorCopy( skel->bones[ j ].t.trans, offset );
					vec3_t forward, right, up;
					QuatToVectorsFRU( skel->bones[ j ].t.rot, forward, right, up );

					VectorSubtract( offset, origin, diff );

					if ( ( length = VectorNormalize( diff ) ) )
					{
						PerpendicularVector( tmp, diff );
						//VectorCopy(up, tmp);

						VectorScale( tmp, length * 0.1, tmp2 );
						VectorMA( tmp2, length * 0.2, diff, tmp2 );

						for ( k = 0; k < 3; k++ )
						{
							RotatePointAroundVector( tmp3, diff, tmp2, k * 120 );
							VectorAdd( tmp3, origin, tmp3 );
							VectorScale( tmp3, skel->scale, tetraVerts[ k ] );
							tetraVerts[ k ][ 3 ] = 1;
						}

						VectorScale( origin, skel->scale, tetraVerts[ 3 ] );
						tetraVerts[ 3 ][ 3 ] = 1;

						Color::Color color = Color::Color::Indexed( j );
						Tess_AddTetrahedron( tetraVerts, color );

						VectorScale( offset, skel->scale, tetraVerts[ 3 ] );
						tetraVerts[ 3 ][ 3 ] = 1;
						Tess_AddTetrahedron( tetraVerts, color );
					}

					MatrixTransformPoint( backEnd.orientation.transformMatrix, skel->bones[ j ].t.trans, worldOrigins[ j ] );
				}

				Tess_End();

#if defined( REFBONE_NAMES )
				if ( cls.consoleFont != nullptr )
				{
					GL_State( GLS_DEPTHTEST_DISABLE | GLS_SRCBLEND_SRC_ALPHA | GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA );

					// go back to the world modelview matrix
					backEnd.orientation = backEnd.viewParms.world;
					GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );
					gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

					// draw names
					for ( j = 0; j < skel->numBones; j++ )
					{
						vec3_t left, up;
						float  radius;
						vec3_t origin;

						// calculate the xyz locations for the four corners
						radius = 0.4;
						VectorScale( backEnd.viewParms.orientation.axis[ 1 ], radius, left );
						VectorScale( backEnd.viewParms.orientation.axis[ 2 ], radius, up );

						if ( backEnd.viewParms.isMirror )
						{
							VectorSubtract( vec3_origin, left, left );
						}

						for ( k = 0; ( unsigned ) k < strlen( skel->bones[ j ].name ); k++ )
						{
							int   ch;

							ch = skel->bones[ j ].name[ k ];
							ch &= 255;

							glyphInfo_t *glyph = &cls.consoleFont->glyphBlock[ 0 ][ ch ];
							re.GlyphChar( cls.consoleFont, ch, glyph );

							shader_t *shader = R_GetShaderByHandle( glyph->glyph );
							if ( shader != tess.surfaceShader )
							{
								// Try to grab an image rather than running the whole q3shader since we
								// want to disable the depth test
								if ( shader->lastStage == shader->stages ||
									!shader->stages[ 0 ].bundle[ TB_COLORMAP ].image[ 0 ] )
								{
									Log::Warn( "can't render bone name '%s'", skel->bones[ j ].name );
									break;
								}

								Tess_End();
								Tess_Begin( Tess_StageIteratorDebug, shader, true, -1 );
								gl_genericShader->SetUniform_ColorMapBindless(
									GL_BindToTMU( 0, shader->stages[ 0 ].bundle[ TB_COLORMAP ].image[ 0 ] )
								);
							}

							VectorMA( worldOrigins[ j ], - ( k*1.8f + 2.0f ), left, origin );
							Tess_AddQuadStampExt( origin, left, up, Color::White, glyph->s,
							                      glyph->t, glyph->s2, glyph->t2 );
						}
					}

					Tess_End();
				}
#endif // REFBONE_NAMES
			}
		}
	}

	// GLSL shader isn't built when reflection mapping is disabled.
	if ( r_showCubeProbes.Get() && glConfig.reflectionMapping &&
	     !( backEnd.refdef.rdflags & ( RDF_NOWORLDMODEL | RDF_NOCUBEMAP ) ) )
	{
		static const vec3_t mins = { -8, -8, -8 };
		static const vec3_t maxs = { 8,  8,  8 };

		static const vec3_t outlineMins = { -9, -9, -9 };
		static const vec3_t outlineMaxs = { 9,  9,  9 };

		// choose right shader program ----------------------------------
		gl_reflectionShader->SetVertexSkinning( false );
		gl_reflectionShader->SetVertexAnimation( false );
		gl_reflectionShader->SetDeform( 0 );
		gl_reflectionShader->BindProgram();

		// end choose right shader program ------------------------------

		gl_reflectionShader->SetUniform_ViewOrigin( backEnd.viewParms.orientation.origin );  // in world space

		GL_State( 0 );
		GL_Cull( cullType_t::CT_FRONT_SIDED );

		// set up the transformation matrix
		backEnd.orientation = backEnd.viewParms.world;
		GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );

		gl_reflectionShader->SetUniform_ModelMatrix( backEnd.orientation.transformMatrix );
		gl_reflectionShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

		if ( r_showCubeProbes.Get() == Util::ordinal( showCubeProbesMode::GRID ) ) {
			// Debug rendering can be really slow here
			for ( auto it = tr.cubeProbeGrid.begin(); it != tr.cubeProbeGrid.end(); it++ ) {
				uint32_t x;
				uint32_t y;
				uint32_t z;
				tr.cubeProbeGrid.IteratorToCoords( it, &x, &y, &z );
				vec3_t position{ ( float ) x * tr.cubeProbeSpacing, ( float ) y * tr.cubeProbeSpacing, ( float ) z * tr.cubeProbeSpacing };

				// Match the map's start coords
				VectorAdd( position, tr.world->nodes[0].mins, position );

				cubemapProbe_t* cubeProbe = &tr.cubeProbes[tr.cubeProbeGrid( x, y, z )];

				Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

				gl_reflectionShader->SetUniform_CameraPosition( position );

				// bind u_ColorMap
				gl_reflectionShader->SetUniform_ColorMapCubeBindless(
					GL_BindToTMU( 0, cubeProbe->cubemap )
				);

				Tess_AddCubeWithNormals( position, mins, maxs, Color::White );

				Tess_End();
			}
		} else {
			for ( const cubemapProbe_t& cubeProbe : tr.cubeProbes ) {

				Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

				gl_reflectionShader->SetUniform_CameraPosition( cubeProbe.origin );

				// bind u_ColorMap
				gl_reflectionShader->SetUniform_ColorMapCubeBindless(
					GL_BindToTMU( 0, cubeProbe.cubemap )
				);

				Tess_AddCubeWithNormals( cubeProbe.origin, mins, maxs, Color::White );

				Tess_End();
			}
		}

		{
			gl_genericShader->SetVertexSkinning( false );
			gl_genericShader->SetVertexAnimation( false );
			gl_genericShader->SetTCGenEnvironment( false );
			gl_genericShader->SetTCGenLightmap( false );
			gl_genericShader->SetDepthFade( false );
			gl_genericShader->SetDeform( 0 );
			gl_genericShader->BindProgram();

			// set uniforms
			gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
			SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
			SetUniform_Color( gl_genericShader, Color::Black );

			GL_State( GLS_DEFAULT );
			GL_Cull( cullType_t::CT_TWO_SIDED );

			// set uniforms

			// set up the transformation matrix
			backEnd.orientation = backEnd.viewParms.world;
			GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );
			gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

			// bind u_ColorMap
			gl_genericShader->SetUniform_ColorMapBindless(
				GL_BindToTMU( 0, tr.whiteImage )
			);
			gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

			GL_State( GLS_POLYMODE_LINE | GLS_DEPTHFUNC_ALWAYS );

			GL_CheckErrors();

			cubemapProbe_t* probes[2];
			vec4_t trilerp;
			vec3_t gridPoints[2];
			R_GetNearestCubeMaps( backEnd.viewParms.orientation.origin, probes, trilerp, 2, gridPoints );

			Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

			vec3_t position;
			if ( r_showCubeProbes.Get() == Util::ordinal( showCubeProbesMode::GRID ) ) {
				VectorSet( position, gridPoints[0][0] * tr.cubeProbeSpacing, gridPoints[0][1] * tr.cubeProbeSpacing,
					gridPoints[0][2] * tr.cubeProbeSpacing );

				// Match the map's start coords
				VectorAdd( position, tr.world->nodes[0].mins, position );
			} else {
				VectorCopy( probes[0]->origin, position );
			}

			Tess_AddCubeWithNormals( position, outlineMins, outlineMaxs, Color::Green );

			if ( r_showCubeProbes.Get() == Util::ordinal( showCubeProbesMode::GRID ) ) {
				VectorSet( position, gridPoints[1][0] * tr.cubeProbeSpacing, gridPoints[1][1] * tr.cubeProbeSpacing,
					gridPoints[1][2] * tr.cubeProbeSpacing );

				// Match the map's start coords
				VectorAdd( position, tr.world->nodes[0].mins, position );
			} else {
				VectorCopy( probes[1]->origin, position );
			}

			Tess_AddCubeWithNormals( position, outlineMins, outlineMaxs, Color::Red );

			Tess_End();
		}

		// go back to the world modelview matrix
		backEnd.orientation = backEnd.viewParms.world;
		GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );
	}

	if ( r_showLightGrid->integer && !( backEnd.refdef.rdflags & RDF_NOWORLDMODEL ) )
	{
		int             x, y, z, k;
		vec3_t          offset;
		vec3_t          tmp, tmp2, tmp3;
		vec_t           length;
		vec4_t          tetraVerts[ 4 ];

		GLIMP_LOGCOMMENT( "--- r_showLightGrid > 0: Rendering light grid" );

		gl_genericShader->SetVertexSkinning( false );
		gl_genericShader->SetVertexAnimation( false );
		gl_genericShader->SetTCGenEnvironment( false );
		gl_genericShader->SetTCGenLightmap( false );
		gl_genericShader->SetDepthFade( false );
		gl_genericShader->SetDeform( 0 );
		gl_genericShader->BindProgram();

		// set uniforms
		gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
		SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_IDENTITY );
		SetUniform_Color( gl_genericShader, Color::Black );

		GL_State( GLS_DEFAULT );
		GL_Cull( cullType_t::CT_TWO_SIDED );

		// set uniforms

		// set up the transformation matrix
		backEnd.orientation = backEnd.viewParms.world;
		GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );
		gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.whiteImage )
		);
		gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

		Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );
		GL_CheckErrors();

		for ( z = 0; z < tr.world->lightGridBounds[ 2 ]; z++ ) {
			for ( y = 0; y < tr.world->lightGridBounds[ 1 ]; y++ ) {
				for ( x = 0; x < tr.world->lightGridBounds[ 0 ]; x++ ) {
					vec3_t origin;
					vec3_t lightDir;

					VectorCopy( tr.world->lightGridOrigin, origin );
					origin[ 0 ] += x * tr.world->lightGridSize[ 0 ];
					origin[ 1 ] += y * tr.world->lightGridSize[ 1 ];
					origin[ 2 ] += z * tr.world->lightGridSize[ 2 ];

					if ( VectorDistanceSquared( origin, backEnd.viewParms.orientation.origin ) > Square( 1024 ) )
					{
						continue;
					}

					// read out grid...
					int gridIndex = x + tr.world->lightGridBounds[ 0 ] * ( y + tr.world->lightGridBounds[ 1 ] * z );
					const bspGridPoint1_t *gp1 = tr.world->lightGridData1 + gridIndex;
					const bspGridPoint2_t *gp2 = tr.world->lightGridData2 + gridIndex;
					lightDir[ 0 ] = snorm8ToFloat( gp2->direction[ 0 ] - 128 );
					lightDir[ 1 ] = snorm8ToFloat( gp2->direction[ 1 ] - 128 );
					lightDir[ 2 ] = snorm8ToFloat( gp2->direction[ 2 ] - 128 );
					Color::Color totalColor = Color::Adapt( gp1->color );
					totalColor *= 1.0f + tr.lightGridAverageCosine;
					float total1Norm = totalColor.Red() + totalColor.Green() + totalColor.Blue();
					float directed1Norm = 3.0f * VectorLength( lightDir );
					float directedFraction = ( tr.lightGridAverageCosine * directed1Norm ) / total1Norm;
					float directedScale = directedFraction / tr.lightGridAverageCosine;
					float ambientScale = 1.0 - directedFraction;
					Color::Color ambientColor = totalColor * ambientScale;
					Color::Color directedColor = totalColor * directedScale;
					VectorNormalize( lightDir );

					VectorNegate( lightDir, lightDir );

					length = 8;
					VectorMA( origin, 8, lightDir, offset );

					PerpendicularVector( tmp, lightDir );
					//VectorCopy(up, tmp);

					VectorScale( tmp, length * 0.1, tmp2 );
					VectorMA( tmp2, length * 0.2, lightDir, tmp2 );

					for ( k = 0; k < 3; k++ )
					{
						RotatePointAroundVector( tmp3, lightDir, tmp2, k * 120 );
						VectorAdd( tmp3, origin, tmp3 );
						VectorCopy( tmp3, tetraVerts[ k ] );
						tetraVerts[ k ][ 3 ] = 1;
					}

					VectorCopy( origin, tetraVerts[ 3 ] );
					tetraVerts[ 3 ][ 3 ] = 1;
					Tess_AddTetrahedron( tetraVerts, ambientColor );

					VectorCopy( offset, tetraVerts[ 3 ] );
					tetraVerts[ 3 ][ 3 ] = 1;
					Tess_AddTetrahedron( tetraVerts, directedColor );
				}
			}
		}

		Tess_End();
	}

	if ( r_showBspNodes->integer )
	{
		if ( ( backEnd.refdef.rdflags & ( RDF_NOWORLDMODEL ) ) || !tr.world )
		{
			return;
		}

		gl_genericShader->SetVertexSkinning( false );
		gl_genericShader->SetVertexAnimation( false );
		gl_genericShader->SetTCGenEnvironment( false );
		gl_genericShader->SetTCGenLightmap( false );
		gl_genericShader->SetDepthFade( false );
		gl_genericShader->SetDeform( 0 );
		gl_genericShader->BindProgram();

		// set uniforms
		gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
		SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_CUSTOM_RGB, alphaGen_t::AGEN_CUSTOM );

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, tr.whiteImage )
		);
		gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

		GL_CheckErrors();

		for ( int i = 0; i < 2; i++ )
		{
			float    x, y, w, h;
			matrix_t ortho;
			vec4_t   quadVerts[ 4 ];

			if ( i == 1 )
			{
				// set 2D virtual screen size
				GL_PushMatrix();
				MatrixOrthogonalProjection( ortho, backEnd.viewParms.viewportX,
				                            backEnd.viewParms.viewportX + backEnd.viewParms.viewportWidth,
				                            backEnd.viewParms.viewportY,
				                            backEnd.viewParms.viewportY + backEnd.viewParms.viewportHeight, -99999, 99999 );
				GL_LoadProjectionMatrix( ortho );

				GL_Cull( cullType_t::CT_TWO_SIDED );
				GL_State( GLS_DEPTHTEST_DISABLE );

				SetUniform_Color( gl_genericShader, Color::Black );

				w = 300;
				h = 300;

				x = 20;
				y = 90;

				Vector4Set( quadVerts[ 0 ], x, y, 0, 1 );
				Vector4Set( quadVerts[ 1 ], x + w, y, 0, 1 );
				Vector4Set( quadVerts[ 2 ], x + w, y + h, 0, 1 );
				Vector4Set( quadVerts[ 3 ], x, y + h, 0, 1 );

				Tess_InstantQuad( *gl_genericShader, x, y, w, h );

				{
					int    j;
					vec3_t farCorners[ 4 ];
					vec3_t nearCorners[ 4 ];
					vec3_t cropBounds[ 2 ];
					vec4_t point, transf;

					GL_Viewport( x, y, w, h );
					GL_Scissor( x, y, w, h );

					GL_PushMatrix();

					// calculate top down view projection matrix
					{
						vec3_t                                                       forward = { 0, 0, -1 };
						vec3_t                                                       up = { 1, 0, 0 };

						matrix_t /*rotationMatrix, transformMatrix,*/ viewMatrix, projectionMatrix;

						// Quake -> OpenGL view matrix from light perspective
						MatrixLookAtRH( viewMatrix, backEnd.viewParms.orientation.origin, forward, up );

						ClearBounds( cropBounds[ 0 ], cropBounds[ 1 ] );

						for ( j = 0; j < 8; j++ )
						{
							point[ 0 ] = tr.world->models[ 0 ].bounds[ j & 1 ][ 0 ];
							point[ 1 ] = tr.world->models[ 0 ].bounds[( j >> 1 ) & 1 ][ 1 ];
							point[ 2 ] = tr.world->models[ 0 ].bounds[( j >> 2 ) & 1 ][ 2 ];
							point[ 3 ] = 1;

							MatrixTransform4( viewMatrix, point, transf );
							transf[ 0 ] /= transf[ 3 ];
							transf[ 1 ] /= transf[ 3 ];
							transf[ 2 ] /= transf[ 3 ];

							AddPointToBounds( transf, cropBounds[ 0 ], cropBounds[ 1 ] );
						}

						MatrixOrthogonalProjectionRH( projectionMatrix, cropBounds[ 0 ][ 0 ], cropBounds[ 1 ][ 0 ], cropBounds[ 0 ][ 1 ], cropBounds[ 1 ][ 1 ], -cropBounds[ 1 ][ 2 ], -cropBounds[ 0 ][ 2 ] );

						GL_LoadModelViewMatrix( viewMatrix );
						GL_LoadProjectionMatrix( projectionMatrix );
					}

					// set uniforms
					SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
					SetUniform_Color( gl_genericShader, Color::Black );

					GL_State( GLS_POLYMODE_LINE | GLS_DEPTHTEST_DISABLE );
					GL_Cull( cullType_t::CT_TWO_SIDED );

					// bind u_ColorMap
					gl_genericShader->SetUniform_ColorMapBindless(
						GL_BindToTMU( 0, tr.whiteImage )
					);
					gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

					gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

					plane_t splitFrustum[ 6 ];
					for ( j = 0; j < 6; j++ )
					{
						VectorCopy( backEnd.viewParms.frustum[ j ].normal, splitFrustum[ j ].normal );
						splitFrustum[ j ].dist = backEnd.viewParms.frustum[ j ].dist;
					}

					// calculate split frustum corner points
					R_CalcFrustumNearCorners( splitFrustum, nearCorners );
					R_CalcFrustumFarCorners( splitFrustum, farCorners );

					Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );

					// draw outer surfaces
					for ( j = 0; j < 4; j++ )
					{
						Vector4Set( quadVerts[ 0 ], nearCorners[ j ][ 0 ], nearCorners[ j ][ 1 ], nearCorners[ j ][ 2 ], 1 );
						Vector4Set( quadVerts[ 1 ], farCorners[ j ][ 0 ], farCorners[ j ][ 1 ], farCorners[ j ][ 2 ], 1 );
						Vector4Set( quadVerts[ 2 ], farCorners[( j + 1 ) % 4 ][ 0 ], farCorners[( j + 1 ) % 4 ][ 1 ], farCorners[( j + 1 ) % 4 ][ 2 ], 1 );
						Vector4Set( quadVerts[ 3 ], nearCorners[( j + 1 ) % 4 ][ 0 ], nearCorners[( j + 1 ) % 4 ][ 1 ], nearCorners[( j + 1 ) % 4 ][ 2 ], 1 );
						Tess_AddQuadStamp2( quadVerts, Color::Cyan );
					}

					// draw far cap
					Vector4Set( quadVerts[ 0 ], farCorners[ 3 ][ 0 ], farCorners[ 3 ][ 1 ], farCorners[ 3 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 1 ], farCorners[ 2 ][ 0 ], farCorners[ 2 ][ 1 ], farCorners[ 2 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 2 ], farCorners[ 1 ][ 0 ], farCorners[ 1 ][ 1 ], farCorners[ 1 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 3 ], farCorners[ 0 ][ 0 ], farCorners[ 0 ][ 1 ], farCorners[ 0 ][ 2 ], 1 );
					Tess_AddQuadStamp2( quadVerts, Color::Blue );

					// draw near cap
					Vector4Set( quadVerts[ 0 ], nearCorners[ 0 ][ 0 ], nearCorners[ 0 ][ 1 ], nearCorners[ 0 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 1 ], nearCorners[ 1 ][ 0 ], nearCorners[ 1 ][ 1 ], nearCorners[ 1 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 2 ], nearCorners[ 2 ][ 0 ], nearCorners[ 2 ][ 1 ], nearCorners[ 2 ][ 2 ], 1 );
					Vector4Set( quadVerts[ 3 ], nearCorners[ 3 ][ 0 ], nearCorners[ 3 ][ 1 ], nearCorners[ 3 ][ 2 ], 1 );
					Tess_AddQuadStamp2( quadVerts, Color::Green );

					Tess_End();

					SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_CUSTOM_RGB, alphaGen_t::AGEN_CUSTOM );
				}
			} // i == 1
			else
			{
				GL_State( GLS_POLYMODE_LINE | GLS_DEPTHTEST_DISABLE );
				GL_Cull( cullType_t::CT_TWO_SIDED );

				// render in world space
				backEnd.orientation = backEnd.viewParms.world;

				GL_LoadProjectionMatrix( backEnd.viewParms.projectionMatrix );
				GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );

				gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );
			}

			// draw BSP nodes
			for ( int j = 0; j < backEndData[ backEnd.smpFrame ]->traversalLength; j++ )
			{
				bspNode_t *node = backEndData[ backEnd.smpFrame ]->traversalList[ j ];

				if ( node->contents != -1 )
				{
					if ( r_showBspNodes->integer == 3 )
					{
						continue;
					}

					if ( node->numMarkSurfaces <= 0 )
					{
						continue;
					}

					//if(node->shrinkedAABB)
					//  SetUniform_Color( gl_genericShader,colorBlue);
					//else
					if ( node->visCounts[ tr.visIndex ] == tr.visCounts[ tr.visIndex ] )
					{
						SetUniform_Color( gl_genericShader, Color::Green );
					}
					else
					{
						SetUniform_Color( gl_genericShader, Color::Red );
					}
				}
				else
				{
					if ( r_showBspNodes->integer == 2 )
					{
						continue;
					}

					if ( node->visCounts[ tr.visIndex ] == tr.visCounts[ tr.visIndex ] )
					{
						SetUniform_Color( gl_genericShader, Color::Yellow );
					}
					else
					{
						SetUniform_Color( gl_genericShader, Color::Blue );
					}
				}

				if ( node->contents != -1 )
				{
					glEnable( GL_POLYGON_OFFSET_FILL );
					GL_PolygonOffset( r_offsetFactor->value, r_offsetUnits->value );
				}

				Tess_Begin( Tess_StageIteratorDebug, nullptr, true, -1 );
				Tess_AddCube( vec3_origin, node->mins, node->maxs, Color::White );
				Tess_End();

				if ( node->contents != -1 )
				{
					glDisable( GL_POLYGON_OFFSET_FILL );
				}
			}

			if ( i == 1 )
			{
				GL_PopMatrix();

				GL_Viewport( backEnd.viewParms.viewportX, backEnd.viewParms.viewportY,
				             backEnd.viewParms.viewportWidth, backEnd.viewParms.viewportHeight );

				GL_Scissor( backEnd.viewParms.scissorX, backEnd.viewParms.scissorY,
				            backEnd.viewParms.scissorWidth, backEnd.viewParms.scissorHeight );

				GL_PopMatrix();
			}
		}

		// go back to the world modelview matrix
		backEnd.orientation = backEnd.viewParms.world;

		GL_LoadProjectionMatrix( backEnd.viewParms.projectionMatrix );
		GL_LoadModelViewMatrix( backEnd.viewParms.world.modelViewMatrix );
	}

	GL_CheckErrors();
}

static unsigned int drawMode;
static debugDrawMode_t currentDebugDrawMode;
static unsigned maxDebugVerts;
static float currentDebugSize;

void DebugDrawBegin( debugDrawMode_t mode, float size ) {

	if ( tess.numVertexes )
	{
		Tess_End();
	}

	Tess_MapVBOs( false );

	Color::Color colorClear = { 0, 0, 0, 0 };
	currentDebugDrawMode = mode;
	currentDebugSize = size;
	switch(mode) {
		case debugDrawMode_t::D_DRAW_POINTS:
			glPointSize( size );
			drawMode = GL_POINTS;
			maxDebugVerts = SHADER_MAX_VERTEXES - 1;
			break;
		case debugDrawMode_t::D_DRAW_LINES:
			glLineWidth( size );
			drawMode = GL_LINES;
			maxDebugVerts = ( SHADER_MAX_VERTEXES - 1 )/2*2;
			break;
		case debugDrawMode_t::D_DRAW_TRIS:
			drawMode = GL_TRIANGLES;
			maxDebugVerts = ( SHADER_MAX_VERTEXES - 1 )/3*3;
			break;
		case debugDrawMode_t::D_DRAW_QUADS:
			drawMode = GL_QUADS;
			maxDebugVerts = ( SHADER_MAX_VERTEXES - 1 )/4*4;
			break;
	}

	gl_genericShader->SetVertexSkinning( false );
	gl_genericShader->SetVertexAnimation( false );
	gl_genericShader->SetTCGenEnvironment( false );
	gl_genericShader->SetTCGenLightmap( false );
	gl_genericShader->SetDepthFade( false );
	gl_genericShader->SetDeform( 0 );
	gl_genericShader->BindProgram();

	GL_State( GLS_SRCBLEND_SRC_ALPHA | GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA );
	GL_Cull( cullType_t::CT_FRONT_SIDED );

	GL_VertexAttribsState( ATTR_POSITION | ATTR_COLOR | ATTR_TEXCOORD );

	// set uniforms
	gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
	SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
	SetUniform_Color( gl_genericShader, colorClear );

	// bind u_ColorMap
	gl_genericShader->SetUniform_ColorMapBindless(
		GL_BindToTMU( 0, tr.whiteImage )
	);
	gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

	// render in world space
	backEnd.orientation = backEnd.viewParms.world;
	GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );
	gl_genericShader->SetUniform_ModelViewProjectionMatrix( glState.modelViewProjectionMatrix[ glState.stackIndex ] );

	GL_CheckErrors();
}

void DebugDrawDepthMask(bool state)
{
	GL_DepthMask( state ? GL_TRUE : GL_FALSE );
}

void DebugDrawVertex(const vec3_t pos, unsigned int color, const vec2_t uv) {
	Color::Color32Bit colors = {
		static_cast<byte>(color & 0xFF),
		static_cast<byte>((color >> 8) & 0xFF),
		static_cast<byte>((color >> 16) & 0xFF),
		static_cast<byte>((color >> 24) & 0xFF)
	};

	//we have reached the maximum number of verts we can batch
	if( tess.numVertexes == maxDebugVerts ) {
		//draw the geometry we already have
		DebugDrawEnd();
		//start drawing again
		DebugDrawBegin(currentDebugDrawMode, currentDebugSize);
	}

	tess.verts[ tess.numVertexes ].xyz[ 0 ] = pos[ 0 ];
	tess.verts[ tess.numVertexes ].xyz[ 1 ] = pos[ 1 ];
	tess.verts[ tess.numVertexes ].xyz[ 2 ] = pos[ 2 ];
	tess.verts[ tess.numVertexes ].color = colors;
	if( uv ) {
		tess.verts[ tess.numVertexes ].texCoords[ 0 ] = uv[ 0 ];
		tess.verts[ tess.numVertexes ].texCoords[ 1 ] = uv[ 1 ];
	}
	tess.indexes[ tess.numIndexes ] = tess.numVertexes;
	tess.numVertexes++;
	tess.numIndexes++;
}

void DebugDrawEnd() {

	Tess_UpdateVBOs( );
	GL_VertexAttribsState( ATTR_POSITION | ATTR_TEXCOORD | ATTR_COLOR );

	if ( glState.currentVBO && glState.currentIBO )
	{
		uintptr_t base = 0;
		if ( glState.currentIBO == tess.ibo )
		{
			base = tess.indexBase * sizeof(glIndex_t);
		}

		glDrawElements( drawMode, tess.numIndexes, GL_INDEX_TYPE, BUFFER_OFFSET( base ) );
		GL_CheckErrors();

		backEnd.pc.c_drawElements++;

		backEnd.pc.c_vboVertexes += tess.numVertexes;
		backEnd.pc.c_vboIndexes += tess.numIndexes;

		backEnd.pc.c_indexes += tess.numIndexes;
		backEnd.pc.c_vertexes += tess.numVertexes;
	}

	Tess_Clear();
	glLineWidth( 1.0f );
	glPointSize( 1.0f );
}

/*
==================
RB_RenderView
==================
*/
static void RB_RenderView( bool depthPass )
{
	GLIMP_LOGCOMMENT( "--- RB_RenderView( %i surfaces ) ---",
		backEnd.viewParms.numDrawSurfs );

	GL_CheckErrors();

	backEnd.pc.c_surfaces += backEnd.viewParms.numDrawSurfs;

	// disable offscreen rendering
	BindMSAAOrMainFBO();

	// we will need to change the projection matrix before drawing
	// 2D images again
	backEnd.projection2D = false;

	// set the modelview matrix for the viewer
	SetViewportAndScissor();

	// ensures that depth writes are enabled for the depth clear
	GL_State( GLS_DEFAULT );

	if ( ( backEnd.refdef.rdflags & RDF_HYPERSPACE ) )
	{
		RB_Hyperspace();

		return;
	}
	else
	{
		backEnd.isHyperspace = false;
	}

	GL_CheckErrors();

	if( depthPass ) {
		if ( glConfig.usingMaterialSystem ) {
			materialSystem.RenderMaterials( shaderSort_t::SS_DEPTH, shaderSort_t::SS_DEPTH, backEnd.viewParms.viewID );
		}
		RB_RenderDrawSurfaces( shaderSort_t::SS_DEPTH, shaderSort_t::SS_DEPTH, DRAWSURFACES_ALL );
		RB_RunVisTests();
		if ( !backEnd.postDepthLightTileRendered && !backEnd.viewParms.hasNestedViews ) {
			RB_RenderPostDepthLightTile();
			backEnd.postDepthLightTileRendered = true;
		}
		return;
	}

	if ( glConfig.usingReadonlyDepth )
	{
		FBO_t *currentDrawFBO = glState.currentFBO;
		R_BindFBO( GL_READ_FRAMEBUFFER, currentDrawFBO );
		R_BindFBO( GL_DRAW_FRAMEBUFFER, tr.readonlyDepthFBO );
		int x0 = backEnd.viewParms.viewportX, x1 = x0 + backEnd.viewParms.viewportWidth;
		int y0 = backEnd.viewParms.viewportY, y1 = y0 + backEnd.viewParms.viewportHeight;
		GL_fboShim.glBlitFramebuffer( x0, y0, x1, y1, x0, y0, x1, y1, GL_DEPTH_BUFFER_BIT, GL_NEAREST );
		R_BindFBO( currentDrawFBO );
	}

	if( tr.refdef.blurVec[0] != 0.0f ||
			tr.refdef.blurVec[1] != 0.0f ||
			tr.refdef.blurVec[2] != 0.0f )
	{
		// draw everything that is not the gun
		if ( glConfig.usingMaterialSystem ) {
			materialSystem.RenderMaterials( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, backEnd.viewParms.viewID );
		}
		RB_RenderDrawSurfaces( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, DRAWSURFACES_ALL_FAR );

		RB_RenderMotionBlur();

		// draw the gun and other "near" stuff
		RB_RenderDrawSurfaces( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, DRAWSURFACES_NEAR_ENTITIES );
	}
	else
	{
		// draw everything that is opaque
		if ( glConfig.usingMaterialSystem ) {
			materialSystem.RenderMaterials( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, backEnd.viewParms.viewID );
		}
		RB_RenderDrawSurfaces( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, DRAWSURFACES_ALL );
	}

	// Here so we don't do an extra MSAA resolve if both SSAO and global fog are present
	// FIXME: global fog is done in a different place now, should this change?
	TransitionMSAAToMain( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );

	RB_RenderSSAO();

	TransitionMainToMSAA( GL_COLOR_BUFFER_BIT );

	// draw everything that is translucent
	if ( glConfig.usingMaterialSystem ) {
		materialSystem.RenderMaterials( shaderSort_t::SS_ENVIRONMENT_NOFOG, shaderSort_t::SS_POST_PROCESS, backEnd.viewParms.viewID );
	}
	RB_RenderDrawSurfaces( shaderSort_t::SS_ENVIRONMENT_NOFOG, shaderSort_t::SS_POST_PROCESS, DRAWSURFACES_ALL );

	GL_CheckErrors();

	// render bloom post process effect
	RB_RenderBloom();

	// render debug information
	RB_RenderDebugUtils();

	if ( backEnd.viewParms.portalLevel > 0 )
	{
		if ( r_liquidMapping->integer )
		{
			// capture current color buffer
			// liquid shader will then bind tr.portalRenderImage
			// as u_PortalMap to be read by liquid glsl
			// FIXME: it does not work
			GL_SelectTexture( 0 );
			GL_Bind( tr.portalRenderImage );
			glCopyTexSubImage2D( GL_TEXTURE_2D, 0, 0, 0, 0, 0, tr.portalRenderImage->uploadWidth, tr.portalRenderImage->uploadHeight );
		}

		backEnd.pc.c_portals++;
	}

	backEnd.pc.c_views++;
}

/*
==================
RB_RenderPostProcess

Present FBO to screen, and render any effects that must go after the main view and its sub views have been rendered
This is done so various debugging facilities will work properly
==================
*/
static void RB_RenderPostProcess()
{
	if ( glConfig.usingMaterialSystem && !r_materialSystemSkip.Get() ) {
		// Dispatch the cull compute shaders for queued once we're done with post-processing
		// We'll only use the results from those shaders in the next frame so we don't block the pipeline
		materialSystem.CullSurfaces();
		materialSystem.EndFrame();
	}

	TransitionMSAAToMain( GL_COLOR_BUFFER_BIT );

	// render chromatic aberration
	RB_CameraPostFX();

	RB_FXAA();

	// copy to given byte buffer that is NOT a FBO
	if ( tr.refdef.pixelTarget != nullptr ) {
		glReadPixels( 0, 0, tr.refdef.pixelTargetWidth, tr.refdef.pixelTargetHeight, GL_RGBA,
			GL_UNSIGNED_BYTE, tr.refdef.pixelTarget );

		for ( int i = 0; i < tr.refdef.pixelTargetWidth * tr.refdef.pixelTargetHeight; i++ ) {
			tr.refdef.pixelTarget[( i * 4 ) + 3] = 255; // Set the alpha to 1.0
		}
	}

	GL_CheckErrors();
}

static void SetFrameUniforms() {
	// This can happen with glsl_restart/vid_restart in R_SyncRenderThread()
	if ( !stagingBuffer.Active() || globalUBOProxy == nullptr ) {
		return;
	}

	GLIMP_LOGCOMMENT( "--- SetFrameUniforms ---" );

	globalUBOProxy->SetUniform_blurVec( tr.refdef.blurVec );
	globalUBOProxy->SetUniform_numLights( tr.refdef.numLights );

	globalUBOProxy->SetUniform_ColorModulate( tr.viewParms.gradingWeights );
	globalUBOProxy->SetUniform_InverseGamma( 1.0f / r_gamma->value );
	globalUBOProxy->SetUniform_Exposure( r_exposure.Get() );

	const bool tonemap = r_toneMapping.Get() && r_highPrecisionRendering.Get() && glConfig.textureFloatAvailable;
	if ( tonemap ) {
		vec4_t tonemapParms{ r_toneMappingContrast.Get(), r_toneMappingHighlightsCompressionSpeed.Get() };
		ComputeTonemapParams( tonemapParms[0], tonemapParms[1], r_toneMappingHDRMax.Get(),
			r_toneMappingDarkAreaPointHDR.Get(), r_toneMappingDarkAreaPointLDR.Get(), tonemapParms[2], tonemapParms[3] );
		globalUBOProxy->SetUniform_TonemapParms( tonemapParms );
	}
	globalUBOProxy->SetUniform_Tonemap( tonemap );

	if ( glConfig.usingMaterialSystem ) {
		materialSystem.SetFrameUniforms();
	}

	if ( !globalUBOProxy->uniformsUpdated ) {
		return;
	}

	uint32_t* data = pushBuffer.MapGlobalUniformData( GLUniform::FRAME );
	globalUBOProxy->WriteUniformsToBuffer( data, GLShader::PUSH, GLUniform::FRAME );

	pushBuffer.PushGlobalUniforms();
}

/*
============================================================================

RENDER BACK END THREAD FUNCTIONS

============================================================================
*/

void RE_UploadCinematic( int cols, int rows, const byte *data, int client, bool dirty )
{
	GL_Bind( tr.cinematicImage[ client ] );

	// if the scratchImage isn't in the format we want, specify it as a new texture
	/* HACK: This also detects we start playing a video to set the appropriate colorspace
	because this assumes a video cannot have a 1×1 size (the RoQ format expects the size
	to be a multiples of 4). */
	if ( cols != tr.cinematicImage[ client ]->width || rows != tr.cinematicImage[ client ]->height )
	{
		tr.cinematicImage[ client ]->width = tr.cinematicImage[ client ]->uploadWidth = cols;
		tr.cinematicImage[ client ]->height = tr.cinematicImage[ client ]->uploadHeight = rows;

		bool isSRGB = tr.worldLinearizeTexture;

		// Makes sure listImages lists the colorspace properly.
		if ( isSRGB )
		{
			tr.cinematicImage[ client ]->bits |= IF_SRGB;
		}
		// No need to delete the bit otherwise because R_InitImages() is called at every map load.

		GL_TexImage2D( GL_TEXTURE_2D, 0, GL_RGB8, cols, rows, 0, GL_RGBA, GL_UNSIGNED_BYTE, data, isSRGB );

		glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
		glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );

		glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER );
		glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER );
		glTexParameterfv( GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, Color::Black.ToArray() );

		// Getting bindless handle makes the texture immutable, so generate it again because we used glTexParameter*
		if ( glConfig.usingBindlessTextures ) {
			tr.cinematicImage[ client ]->texture->GenBindlessHandle();
		}
	}
	else
	{
		if ( dirty )
		{
			// otherwise, just subimage upload it so that drivers can tell we are going to be changing
			// it and don't try and do a texture compression
			glTexSubImage2D( GL_TEXTURE_2D, 0, 0, 0, cols, rows, GL_RGBA, GL_UNSIGNED_BYTE, data );
		}
	}

	GL_CheckErrors();
}

/*
=============
RB_SetColor
=============
*/
const RenderCommand *SetColorCommand::ExecuteSelf() const
{
	GLIMP_LOGCOMMENT( "--- SetColorCommand::ExecuteSelf ---" );

	backEnd.color2D = color;

	return this + 1;
}

/*
=============
RB_SetColorGrading
=============
*/
const RenderCommand *SetColorGradingCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- SetColorGradingCommand::ExecuteSelf ---" );

	if( slot < 0 || slot >= REF_COLORGRADE_SLOTS ) {
		return this + 1;
	}

	if( glState.colorgradeSlots[ slot ] == image ) {
		return this + 1;
	}

	GL_Bind( image );

	glBindBuffer( GL_PIXEL_PACK_BUFFER, tr.colorGradePBO );

	glGetTexImage( image->type, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr );
	glBindBuffer( GL_PIXEL_PACK_BUFFER, 0 );

	glBindBuffer( GL_PIXEL_UNPACK_BUFFER, tr.colorGradePBO );

	GL_Bind( tr.colorGradeImage );

	if ( image->width == REF_COLORGRADEMAP_SIZE )
	{
		glTexSubImage3D( GL_TEXTURE_3D, 0, 0, 0, slot * REF_COLORGRADEMAP_SIZE,
		                 REF_COLORGRADEMAP_SIZE, REF_COLORGRADEMAP_SIZE, REF_COLORGRADEMAP_SIZE,
		                 GL_RGBA, GL_UNSIGNED_BYTE, nullptr );
	}
	else
	{
		int i;

		glPixelStorei( GL_UNPACK_ROW_LENGTH, REF_COLORGRADEMAP_SIZE * REF_COLORGRADEMAP_SIZE );

		for ( i = 0; i < 16; i++ )
		{
			glTexSubImage3D( GL_TEXTURE_3D, 0, 0, 0, i + slot * REF_COLORGRADEMAP_SIZE,
			                 REF_COLORGRADEMAP_SIZE, REF_COLORGRADEMAP_SIZE, 1,
			                 GL_RGBA, GL_UNSIGNED_BYTE, BUFFER_OFFSET( sizeof(u8vec4_t) * REF_COLORGRADEMAP_SIZE ) );
		}

		glPixelStorei( GL_UNPACK_ROW_LENGTH, 0 );
	}

	glBindBuffer( GL_PIXEL_UNPACK_BUFFER, 0 );

	glState.colorgradeSlots[ slot ] = image;

	return this + 1;
}

/*
=============
RB_StretchPic
=============
*/
const RenderCommand *StretchPicCommand::ExecuteSelf( ) const
{
	int                       numVerts, numIndexes;

	GLIMP_LOGCOMMENT( "--- StretchPicCommand::ExecuteSelf ---" );

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	if ( shader != tess.surfaceShader )
	{
		if ( tess.numIndexes )
		{
			Tess_End();
		}

		backEnd.currentEntity = &backEnd.entity2D;
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	if( !tess.indexes ) {
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	Tess_CheckOverflow( 4, 6 );
	numVerts = tess.numVertexes;
	numIndexes = tess.numIndexes;

	tess.numVertexes += 4;
	tess.numIndexes += 6;

	tess.indexes[ numIndexes ] = numVerts + 3;
	tess.indexes[ numIndexes + 1 ] = numVerts + 0;
	tess.indexes[ numIndexes + 2 ] = numVerts + 2;
	tess.indexes[ numIndexes + 3 ] = numVerts + 2;
	tess.indexes[ numIndexes + 4 ] = numVerts + 0;
	tess.indexes[ numIndexes + 5 ] = numVerts + 1;

	tess.verts[ numVerts ].xyz[ 0 ] = x;
	tess.verts[ numVerts ].xyz[ 1 ] = y;
	tess.verts[ numVerts ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 0 ].color = backEnd.color2D;

	tess.verts[ numVerts ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 1 ].xyz[ 0 ] = x + w;
	tess.verts[ numVerts + 1 ].xyz[ 1 ] = y;
	tess.verts[ numVerts + 1 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 1 ].color = backEnd.color2D;

	tess.verts[ numVerts + 1 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 1 ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 2 ].xyz[ 0 ] = x + w;
	tess.verts[ numVerts + 2 ].xyz[ 1 ] = y + h;
	tess.verts[ numVerts + 2 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 2 ].color = backEnd.color2D;

	tess.verts[ numVerts + 2 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 2 ].texCoords[ 1 ] = t2;

	tess.verts[ numVerts + 3 ].xyz[ 0 ] = x;
	tess.verts[ numVerts + 3 ].xyz[ 1 ] = y + h;
	tess.verts[ numVerts + 3 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 3 ].color = backEnd.color2D;

	tess.verts[ numVerts + 3 ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts + 3 ].texCoords[ 1 ] = t2;

	return this + 1;
}

const RenderCommand *ScissorSetCommand::ExecuteSelf( ) const {
	tr.scissor.x = x;
	tr.scissor.y = y;
	tr.scissor.w = w;
	tr.scissor.h = h;

	Tess_End();
	GL_Scissor( x, y, w, h );
	tess.surfaceShader = nullptr;

	return this + 1;
}

const RenderCommand *Poly2dCommand::ExecuteSelf( ) const
{
	int                   i;

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	if ( shader != tess.surfaceShader )
	{
		if ( tess.numIndexes )
		{
			Tess_End();
		}

		backEnd.currentEntity = &backEnd.entity2D;
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	Tess_CheckOverflow( numverts, ( numverts - 2 ) * 3 );

	for ( i = 0; i < numverts - 2; i++ )
	{
		tess.indexes[ tess.numIndexes + 0 ] = tess.numVertexes;
		tess.indexes[ tess.numIndexes + 1 ] = tess.numVertexes + i + 1;
		tess.indexes[ tess.numIndexes + 2 ] = tess.numVertexes + i + 2;
		tess.numIndexes += 3;
	}

	for ( i = 0; i < numverts; i++ )
	{
		tess.verts[ tess.numVertexes ].xyz[ 0 ] = verts[ i ].xyz[ 0 ];
		tess.verts[ tess.numVertexes ].xyz[ 1 ] = verts[ i ].xyz[ 1 ];
		tess.verts[ tess.numVertexes ].xyz[ 2 ] = 0.0f;

		tess.verts[ tess.numVertexes ].texCoords[ 0 ] = verts[ i ].st[ 0 ];
		tess.verts[ tess.numVertexes ].texCoords[ 1 ] = verts[ i ].st[ 1 ];

		Color::Color32Bit color = Color::Adapt( verts[ i ].modulate );
		color = tr.convertColorFromSRGB( color );
		tess.verts[ tess.numVertexes ].color = color;

		tess.numVertexes++;
	}

	return this + 1;
}

const RenderCommand *Poly2dIndexedCommand::ExecuteSelf( ) const
{
	cullType_t            oldCullType;
	int                   i;

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	// HACK: Our shader system likes to cull things that we'd like shown
	oldCullType = shader->cullType;
	shader->cullType = CT_TWO_SIDED;

	if ( shader != tess.surfaceShader )
	{
		if ( tess.numIndexes )
		{
			Tess_End();
		}

		backEnd.currentEntity = &backEnd.entity2D;
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	if( !tess.verts ) {
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	Tess_CheckOverflow( numverts, numIndexes );

	for ( i = 0; i < numIndexes; i++ )
	{
		tess.indexes[ tess.numIndexes + i ] = tess.numVertexes + indexes[ i ];
	}
	tess.numIndexes += numIndexes;
	if ( tr.scissor.status )
	{
		GL_Scissor( tr.scissor.x, tr.scissor.y, tr.scissor.w, tr.scissor.h );
	}

	for ( i = 0; i < numverts; i++ )
	{
		tess.verts[ tess.numVertexes ].xyz[ 0 ] = verts[ i ].xyz[ 0 ] + translation[ 0 ];
		tess.verts[ tess.numVertexes ].xyz[ 1 ] = verts[ i ].xyz[ 1 ] + translation[ 1 ];
		tess.verts[ tess.numVertexes ].xyz[ 2 ] = 0.0f;

		tess.verts[ tess.numVertexes ].texCoords[ 0 ] = verts[ i ].st[ 0 ];
		tess.verts[ tess.numVertexes ].texCoords[ 1 ] = verts[ i ].st[ 1 ];

		Color::Color32Bit color = Color::Adapt( verts[ i ].modulate );
		color = tr.convertColorFromSRGB( color );
		tess.verts[ tess.numVertexes ].color = color;

		tess.numVertexes++;
	}

	shader->cullType = oldCullType;

	return this + 1;
}

static bool pushed = false;
const RenderCommand *SetMatrixTransformCommand::ExecuteSelf() const {
	Tess_End();
	// HACK: Currently, this is only used for RmlUI. We have a maximum
	// of MAX_GLSTACK matrices we can have on our matrix stack. RmlUI can
	// sometimes push more than 4 causing a crash. However, RmlUI doesn't
	// need the push/pop nature, since it sends premultiplied matrices.
	// Therefore, we only need to push one matrix, and overwrite it every
	// new call, until we get a call to reset, then we pop it.
	if (!pushed)
	{
		GL_PushMatrix();
		pushed = true;
	}
	// Copy the previous project matrix to the current stack.
	MatrixCopy( glState.projectionMatrix[ glState.stackIndex - 1 ],
	            glState.projectionMatrix[ glState.stackIndex ] );
	// Load our new transformation matrix.
	GL_LoadModelViewMatrix( this->matrix );
	tess.surfaceShader = nullptr;
	return this + 1;
}

const RenderCommand *ResetMatrixTransformCommand::ExecuteSelf() const {
	if (!pushed) return this + 1;
	Tess_End();
	GL_PopMatrix();
	pushed = false;
	return this + 1;
}

// NERVE - SMF

/*
=============
RB_RotatedPic
=============
*/
const RenderCommand *RotatedPicCommand::ExecuteSelf( ) const
{
	int                       numVerts, numIndexes;
	float                     mx, my, cosA, sinA, cw, ch, sw, sh;

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	if ( shader != tess.surfaceShader )
	{
		if ( tess.numIndexes )
		{
			Tess_End();
		}

		backEnd.currentEntity = &backEnd.entity2D;
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	if( !tess.indexes ) {
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	Tess_CheckOverflow( 4, 6 );
	numVerts = tess.numVertexes;
	numIndexes = tess.numIndexes;

	tess.numVertexes += 4;
	tess.numIndexes += 6;

	tess.indexes[ numIndexes ] = numVerts + 3;
	tess.indexes[ numIndexes + 1 ] = numVerts + 0;
	tess.indexes[ numIndexes + 2 ] = numVerts + 2;
	tess.indexes[ numIndexes + 3 ] = numVerts + 2;
	tess.indexes[ numIndexes + 4 ] = numVerts + 0;
	tess.indexes[ numIndexes + 5 ] = numVerts + 1;

	mx = x + ( w / 2 );
	my = y + ( h / 2 );
	cosA = cosf( DEG2RAD( angle ) );
	sinA = sinf( DEG2RAD( angle ) );
	cw = cosA * ( w / 2 );
	ch = cosA * ( h / 2 );
	sw = sinA * ( w / 2 );
	sh = sinA * ( h / 2 );

	tess.verts[ numVerts ].xyz[ 0 ] = mx - cw - sh;
	tess.verts[ numVerts ].xyz[ 1 ] = my + sw - ch;
	tess.verts[ numVerts ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 0 ].color = backEnd.color2D;

	tess.verts[ numVerts ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 1 ].xyz[ 0 ] = mx + cw - sh;
	tess.verts[ numVerts + 1 ].xyz[ 1 ] = my - sw - ch;
	tess.verts[ numVerts + 1 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 1 ].color = backEnd.color2D;

	tess.verts[ numVerts + 1 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 1 ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 2 ].xyz[ 0 ] = mx + cw + sh;
	tess.verts[ numVerts + 2 ].xyz[ 1 ] = my - sw + ch;
	tess.verts[ numVerts + 2 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 2 ].color = backEnd.color2D;

	tess.verts[ numVerts + 2 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 2 ].texCoords[ 1 ] = t2;

	tess.verts[ numVerts + 3 ].xyz[ 0 ] = mx - cw + sh;
	tess.verts[ numVerts + 3 ].xyz[ 1 ] = my + sw + ch;
	tess.verts[ numVerts + 3 ].xyz[ 2 ] = 0.0f;
	tess.verts[ numVerts + 3 ].color = backEnd.color2D;

	tess.verts[ numVerts + 3 ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts + 3 ].texCoords[ 1 ] = t2;

	return this + 1;
}

// -NERVE - SMF

/*
==============
RB_StretchPicGradient
==============
*/
const RenderCommand *GradientPicCommand::ExecuteSelf( ) const
{
	int                       numVerts, numIndexes;

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	if ( shader != tess.surfaceShader )
	{
		if ( tess.numIndexes )
		{
			Tess_End();
		}

		backEnd.currentEntity = &backEnd.entity2D;
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	if( !tess.indexes ) {
		Tess_Begin( Tess_StageIteratorColor, shader, false, -1 );
	}

	Tess_CheckOverflow( 4, 6 );
	numVerts = tess.numVertexes;
	numIndexes = tess.numIndexes;

	tess.numVertexes += 4;
	tess.numIndexes += 6;

	tess.indexes[ numIndexes ] = numVerts + 3;
	tess.indexes[ numIndexes + 1 ] = numVerts + 0;
	tess.indexes[ numIndexes + 2 ] = numVerts + 2;
	tess.indexes[ numIndexes + 3 ] = numVerts + 2;
	tess.indexes[ numIndexes + 4 ] = numVerts + 0;
	tess.indexes[ numIndexes + 5 ] = numVerts + 1;

	tess.verts[ numVerts + 0 ].color = backEnd.color2D;
	tess.verts[ numVerts + 1 ].color = backEnd.color2D;
	tess.verts[ numVerts + 2 ].color = gradientColor;
	tess.verts[ numVerts + 3 ].color = gradientColor;

	tess.verts[ numVerts ].xyz[ 0 ] = x;
	tess.verts[ numVerts ].xyz[ 1 ] = y;
	tess.verts[ numVerts ].xyz[ 2 ] = 0.0f;

	tess.verts[ numVerts ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 1 ].xyz[ 0 ] = x + w;
	tess.verts[ numVerts + 1 ].xyz[ 1 ] = y;
	tess.verts[ numVerts + 1 ].xyz[ 2 ] = 0.0f;

	tess.verts[ numVerts + 1 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 1 ].texCoords[ 1 ] = t1;

	tess.verts[ numVerts + 2 ].xyz[ 0 ] = x + w;
	tess.verts[ numVerts + 2 ].xyz[ 1 ] = y + h;
	tess.verts[ numVerts + 2 ].xyz[ 2 ] = 0.0f;

	tess.verts[ numVerts + 2 ].texCoords[ 0 ] = s2;
	tess.verts[ numVerts + 2 ].texCoords[ 1 ] = t2;

	tess.verts[ numVerts + 3 ].xyz[ 0 ] = x;
	tess.verts[ numVerts + 3 ].xyz[ 1 ] = y + h;
	tess.verts[ numVerts + 3 ].xyz[ 2 ] = 0.0f;

	tess.verts[ numVerts + 3 ].texCoords[ 0 ] = s1;
	tess.verts[ numVerts + 3 ].texCoords[ 1 ] = t2;

	return this + 1;
}

/*
=============
RB_SetupLights
=============
*/
const RenderCommand *SetupLightsCommand::ExecuteSelf() const
{
	GLenum bufferTarget = glConfig.uniformBufferObjectAvailable ? GL_UNIFORM_BUFFER : GL_PIXEL_UNPACK_BUFFER;

	GLIMP_LOGCOMMENT( "--- SetupLightsCommand::ExecuteSelf ---" );

	const int numLights = refdef.numLights;
	if( numLights ) {
		shaderLight_t *buffer;

		glBindBuffer( bufferTarget, tr.dlightUBO );
		buffer = (shaderLight_t *) glMapBufferRange( bufferTarget,
							    0, numLights * sizeof( shaderLight_t ),
							    GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT );

		for( int i = 0, j = 0; i < numLights; i++, j++ ) {
			refLight_t *light = &refdef.lights[j];

			VectorCopy( light->origin, buffer[i].center );
			buffer[i].radius = light->radius;
			VectorCopy( light->color, buffer[i].color );

			buffer[i].type = Util::ordinal( light->rlType );
			switch( light->rlType ) {
				case refLightType_t::RL_PROJ:
					VectorCopy( light->projTarget, buffer[i].direction );
					buffer[i].angle = cosf( atan2f( VectorLength( light->projUp), VectorLength( light->projTarget ) ) );
					break;
				case refLightType_t::RL_DIRECTIONAL:
					VectorCopy( light->projTarget, buffer[i].direction );
					break;
				default:
					break;
			}
		}

		glUnmapBuffer( bufferTarget );
		glBindBuffer( bufferTarget, 0 );
	}

	return this + 1;
}

/*
=============
RB_ClearBuffer
=============
*/
const RenderCommand *ClearBufferCommand::ExecuteSelf( ) const
{
	int clearBits = GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT;

	GLIMP_LOGCOMMENT( "--- ClearBufferCommand::ExecuteSelf ---" );

	// finish any 2D drawing if needed
	Tess_End();

	backEnd.refdef = refdef;
	backEnd.viewParms = viewParms;
	backEnd.postDepthLightTileRendered = false;

	GL_CheckErrors();

	// sync with gl if needed
	if ( r_finish->integer == 1 && !glState.finishCalled )
	{
		glFinish();
		glState.finishCalled = true;
	}

	if ( r_finish->integer == 0 )
	{
		glState.finishCalled = true;
	}

	// disable offscreen rendering
	R_BindFBO( tr.mainFBO[backEnd.currentMainFBO] );

	// we will need to change the projection matrix before drawing
	// 2D images again
	backEnd.projection2D = false;

	backEnd.dirtyDepthBuffer = false;

	// set the modelview matrix for the viewer
	SetViewportAndScissor();

	// ensures that depth writes are enabled for the depth clear
	GL_State( GLS_DEFAULT );

	// Clear relevant buffers, not drawing the sky always require clearing.
	if ( r_clear.Get() || !r_drawSky.Get() ) {
		clearBits |= GL_COLOR_BUFFER_BIT;
	}

	glClear( clearBits );

	if ( glConfig.MSAA ) {
		R_BindFBO( tr.msaaFBO );
		glClear( clearBits );
	}

	return this + 1;
}

/*
=============
RB_PreparePortal
=============
*/
const RenderCommand *PreparePortalCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- PreparePortalCommand::ExecuteSelf ---" );

	backEnd.refdef = refdef;
	backEnd.viewParms = viewParms;
	shader_t *shader = surface->shader;

	// set the modelview matrix for the viewer
	SetViewportAndScissor();

	if ( surface->entity != &tr.worldEntity )
	{
		backEnd.currentEntity = surface->entity;

		// set up the transformation matrix
		R_RotateEntityForViewParms( backEnd.currentEntity, &backEnd.viewParms, &backEnd.orientation );
	}
	else
	{
		backEnd.currentEntity = &tr.worldEntity;
		backEnd.orientation = backEnd.viewParms.world;
	}

	GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );

	if ( backEnd.viewParms.portalLevel == 0 ) {
		glEnable( GL_STENCIL_TEST );
		glStencilMask( 0xff );
	}

	glStencilFunc( GL_EQUAL, backEnd.viewParms.portalLevel, 0xff );
	glStencilOp( GL_KEEP, GL_KEEP, GL_INCR );

	GL_State( GLS_COLORMASK_BITS );
	glState.glStateBitsMask = GLS_COLORMASK_BITS;

	Tess_Begin( Tess_StageIteratorPortal, shader, false, -1 );
	rb_surfaceTable[Util::ordinal(*(surface->surface))](surface->surface );
	Tess_End();

	glState.glStateBitsMask = 0;

	// set depth to max on portal area
	glDepthRange( 1.0f, 1.0f );

	glStencilFunc( GL_EQUAL, backEnd.viewParms.portalLevel + 1, 0xff );
	glStencilOp( GL_KEEP, GL_KEEP, GL_KEEP );

	GL_State( GLS_DEPTHMASK_TRUE | GLS_COLORMASK_BITS | GLS_DEPTHFUNC_ALWAYS);
	glState.glStateBitsMask = GLS_DEPTHMASK_TRUE | GLS_COLORMASK_BITS | GLS_DEPTHFUNC_ALWAYS;

	Tess_Begin( Tess_StageIteratorPortal, shader, false, -1 );
	rb_surfaceTable[Util::ordinal(*(surface->surface))](surface->surface );
	Tess_End();

	glState.glStateBitsMask = 0;

	glDepthRange( 0.0f, 1.0f );

	// keep stencil test enabled !

	return this + 1;
}

/*
=============
RB_FinalisePortal
=============
*/
const RenderCommand *FinalisePortalCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- FinalisePortalCommand::ExecuteSelf ---" );

	backEnd.refdef = refdef;
	backEnd.viewParms = viewParms;
	shader_t *shader = surface->shader;

	// set the modelview matrix for the viewer
	SetViewportAndScissor();

	if ( surface->entity != &tr.worldEntity )
	{
		backEnd.currentEntity = surface->entity;

		// set up the transformation matrix
		R_RotateEntityForViewParms( backEnd.currentEntity, &backEnd.viewParms, &backEnd.orientation );
	}
	else
	{
		backEnd.currentEntity = &tr.worldEntity;
		backEnd.orientation = backEnd.viewParms.world;
	}

	GL_LoadModelViewMatrix( backEnd.orientation.modelViewMatrix );

	GL_State( GLS_DEPTHMASK_TRUE | GLS_DEPTHFUNC_ALWAYS );
	glState.glStateBitsMask = GLS_DEPTHMASK_TRUE | GLS_DEPTHFUNC_ALWAYS;

	glStencilFunc( GL_EQUAL, backEnd.viewParms.portalLevel + 1, 0xff );
	glStencilOp( GL_KEEP, GL_KEEP, GL_KEEP );

	Tess_Begin( Tess_StageIteratorColor, shader,
		false, surface->lightmapNum(), surface->bspSurface );
	rb_surfaceTable[Util::ordinal( *( surface->surface ) )]( surface->surface );
	Tess_End();

	glStencilOp( GL_KEEP, GL_KEEP, GL_DECR );

	GL_State( GLS_COLORMASK_BITS | GLS_DEPTHFUNC_ALWAYS);
	glState.glStateBitsMask = GLS_COLORMASK_BITS | GLS_DEPTHFUNC_ALWAYS;

	Tess_Begin( Tess_StageIteratorPortal, shader, false, -1 );
	rb_surfaceTable[Util::ordinal(*(surface->surface))](surface->surface );
	Tess_End();

	glStencilFunc( GL_EQUAL, backEnd.viewParms.portalLevel, 0xff );
	glStencilOp( GL_KEEP, GL_KEEP, GL_KEEP );

	glState.glStateBitsMask = 0;

	if( backEnd.viewParms.portalLevel == 0 ) {
		glDisable( GL_STENCIL_TEST );
	}

	return this + 1;
}

/*
=============
RB_DrawView
=============
*/
const RenderCommand *DrawViewCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- DrawViewCommand::ExecuteSelf ---" );

	// finish any 2D drawing if needed
	Tess_End();

	backEnd.refdef = refdef;
	backEnd.viewParms = viewParms;

	RB_RenderView( depthPass );

	return this + 1;
}

/*
=============
RB_DrawPostProcess
=============
*/
const RenderCommand *RenderPostProcessCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- RenderPostProcessCommand::ExecuteSelf ---" );

	// finish any 3D drawing if needed
	if (tess.numIndexes)
	{
		Tess_End();
	}

	backEnd.refdef = refdef;
	backEnd.viewParms = viewParms;

	RB_RenderPostProcess();

	return this + 1;
}

/*
=============
RB_DrawBuffer
=============
*/
const RenderCommand *DrawBufferCommand::ExecuteSelf( ) const
{
	GLIMP_LOGCOMMENT( "--- DrawBufferCommand::ExecuteSelf ---" );

	GL_DrawBuffer( buffer );

	glState.finishCalled = false;
	return this + 1;
}

/*
===============
RB_ShowImages

Draw all the images to the screen, on top of whatever
was there.  This is used to test for texture thrashing.

Also called by RE_EndRegistration
===============
*/
void RB_ShowImages()
{
	image_t *image;
	float   x, y, w, h;
	int     start, end;

	GLIMP_LOGCOMMENT( "--- RB_ShowImages ---" );

	if ( !backEnd.projection2D )
	{
		RB_SetGL2D();
	}

	glClear( GL_COLOR_BUFFER_BIT );

	glFinish();

	gl_genericShader->SetVertexSkinning( false );
	gl_genericShader->SetVertexAnimation( false );
	gl_genericShader->SetTCGenEnvironment( false );
	gl_genericShader->SetTCGenLightmap( false );
	gl_genericShader->SetDepthFade( false );
	gl_genericShader->SetDeform( 0 );
	gl_genericShader->BindProgram();

	GL_Cull( cullType_t::CT_TWO_SIDED );

	// set uniforms
	gl_genericShader->SetUniform_AlphaTest( GLS_ATEST_NONE );
	SetUniform_ColorModulateColorGen( gl_genericShader, colorGen_t::CGEN_VERTEX, alphaGen_t::AGEN_VERTEX );
	gl_genericShader->SetUniform_TextureMatrix( matrixIdentity );

	GL_SelectTexture( 0 );

	start = ri.Milliseconds();

	matrix_t ortho;
	GL_PushMatrix();
	MatrixOrthogonalProjection( ortho, backEnd.viewParms.viewportX,
		backEnd.viewParms.viewportX + backEnd.viewParms.viewportWidth,
		backEnd.viewParms.viewportY,
		backEnd.viewParms.viewportY + backEnd.viewParms.viewportHeight, -99999, 99999 );
	GL_LoadProjectionMatrix( ortho );

	for ( size_t i = 0; i < tr.images.size(); i++ )
	{
		image = tr.images[ i ];

		/*
		   if(image->bits & (IF_RGBA16F | IF_RGBA32F | IF_LA16F | IF_LA32F))
		   {
		   // don't render float textures using FFP
		   continue;
		   }
		 */

		w = windowConfig.vidWidth / 20;
		h = windowConfig.vidHeight / 15;
		x = i % 20 * w;
		y = i / 20 * h;

		// show in proportional size in mode 2
		if ( r_showImages->integer == 2 )
		{
			w *= image->uploadWidth / 512.0f;
			h *= image->uploadHeight / 512.0f;
		}

		// bind u_ColorMap
		gl_genericShader->SetUniform_ColorMapBindless(
			GL_BindToTMU( 0, image )
		);

		Tess_InstantQuad( *gl_genericShader, x, y, w, h );
	}

	GL_PopMatrix();

	glFinish();

	end = ri.Milliseconds();
	Log::Debug("%i msec to draw all images", end - start );

	GL_CheckErrors();
}

/*
=============
RB_SwapBuffers
=============
*/
const RenderCommand *SwapBuffersCommand::ExecuteSelf( ) const
{
	// finish any 2D drawing if needed
	Tess_End();

	// texture swapping test
	if ( r_showImages->integer )
	{
		RB_ShowImages();
	}

	GLimp_EndFrame();

	backEnd.projection2D = false;

	return this + 1;
}

/*
=============
R_ShutdownBackend
=============
*/
void R_ShutdownBackend()
{
	int i;

	for ( i = 0; i < ATTR_INDEX_MAX; i++ )
	{
		glDisableVertexAttribArray( i );
	}
	glState.vertexAttribsState = 0;

	if ( tr.linearSampler )
	{
		glDeleteSamplers( 1, &tr.linearSampler );
		tr.linearSampler = 0;
	}
}

const RenderCommand *EndOfListCommand::ExecuteSelf( ) const
{
	return nullptr;
}

/*
====================
RB_ExecuteRenderCommands

This function will be called synchronously if running without
smp extensions, or asynchronously by another thread.
====================
*/
void RB_ExecuteRenderCommands( const void *data )
{
	const RenderCommand *cmd = (const RenderCommand *)data;
	int t1, t2;

	GLIMP_LOGCOMMENT( "--- RB_ExecuteRenderCommands ---" );

	t1 = ri.Milliseconds();

	if ( !r_smp->integer || data == backEndData[ 0 ]->commands.cmds )
	{
		backEnd.smpFrame = 0;
	}
	else
	{
		backEnd.smpFrame = 1;
	}


	materialSystem.frameStart = true;

	if ( glConfig.pushBufferAvailable ) {
		SetFrameUniforms();
	}

	while ( cmd != nullptr )
	{
		cmd = cmd->ExecuteSelf();
	}

	// stop rendering on this thread
	t2 = ri.Milliseconds();
	backEnd.pc.msec = t2 - t1;
	return;
}

/*
================
RB_RenderThread
================
*/
void RB_RenderThread()
{
	const void *data;

	// wait for either a rendering command or a quit command
	while ( true )
	{
		// sleep until we have work to do
		data = GLimp_RendererSleep();

		if ( !data )
		{
			return; // all done, renderer is shutting down
		}

		Omp::EnlistThreads();

		renderThreadActive = true;

		RB_ExecuteRenderCommands( data );

		renderThreadActive = false;
	}
}